685431331200 has 1920 divisors, whose sum is σ = 3210918416640. Its totient is φ = 139843584000.

The previous prime is 685431331187. The next prime is 685431331213. The reversal of 685431331200 is 2133134586.

685431331200 is a `hidden beast` number, since 6 + 85 + 43 + 1 + 331 + 200 = 666.

It is an interprime number because it is at equal distance from previous prime (685431331187) and next prime (685431331213).

It is a tau number, because it is divible by the number of its divisors (1920).

It is a super-2 number, since 2×685431331200² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 1217462119 + ... + 1217462681.

It is an arithmetic number, because the mean of its divisors is an integer number (1672353342).

Almost surely, 2^685431331200 is an apocalyptic number.

685431331200 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 685431331200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1605459208320).

685431331200 is an abundant number, since it is smaller than the sum of its proper divisors (2525487085440).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

685431331200 is a wasteful number, since it uses less digits than its factorization.

685431331200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 678 (or 652 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

Adding to 685431331200 its reverse (2133134586), we get a palindrome (687564465786).

The spelling of 685431331200 in words is "six hundred eighty-five billion, four hundred thirty-one million, three hundred thirty-one thousand, two hundred".