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
Root race island called the "white island" in the middle of what was then an inland sea in what is now the Gobi desert, where they established the "City of the Bridge". (The "City of the Bridge" was constructed directly below the etheric city called Shamballa where Theosophists believe the governing deity of Earth, Sanat Kumara, dwells; thus, the ongoing evolution of the Aryan root race has been divinely guided by the being Theosophists call "The Lord of the World".) The esoteric name of the whole of the present land surface of Earth, i.e. the World Island, the Americas, the Australian continent