400 (number) third perfect number, a number whose divisors add up to the actual number (1+2+4+8+16+31+62+124+248=496). 497 = 7 × 71, sum of five consecutive primes (89 + 97 + 101 + 103 + 107) 498 = 2 × 3 × 83, sphenic number, untouchable number, admirable number, abundant number A prime number, Chen prime 400 (number) 400 (four hundred) is the natural number following 399 and preceding 401. 400 is the square of 20. 400 is the sum of the powers of 7 from 0 to 3, thus making it a repdigit in base 7 (1111). A circle is divided into
Southern Railway 401 Southern Railway 401 Southern Railway 401 is a steam locomotive built in December 1907 by Baldwin Locomotive Works for Southern Railway. It is a 2-8-0 Consolidation of Southern's H-4 class. 401 is one of 25 class H-4 2-8-0 Consolidation Type steam locomotives built by the Baldwin Locomotive Works of Philadelphia, Pennsylvania in November 1907 for the Southern Railroad to haul freight trains. In 1949, #401 was sold to the Alabama Asphaltic Limestone Company in Margerum, Alabama. She switched hopper cars of stone until the company brought in a diesel in 1963, then she was placed on stand-by service in case