668503490931 has 16 divisors (see below), whose sum is σ = 1001503360800. Its totient is φ = 440661475584.

The previous prime is 668503490927. The next prime is 668503490947. The reversal of 668503490931 is 139094305866.

668503490931 is a `hidden beast` number, since 6 + 6 + 8 + 503 + 49 + 0 + 93 + 1 = 666.

It is not a de Polignac number, because 668503490931 - 2² = 668503490927 is a prime.

It is a super-2 number, since 2×668503490931² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (668503490981) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 139095286 + ... + 139100091.

It is an arithmetic number, because the mean of its divisors is an integer number (62593960050).

Almost surely, 2^668503490931 is an apocalyptic number.

668503490931 is a deficient number, since it is larger than the sum of its proper divisors (332999869869).

668503490931 is a wasteful number, since it uses less digits than its factorization.

668503490931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278195475 (or 278195469 counting only the distinct ones).

The product of its (nonzero) digits is 4199040, while the sum is 54.

The spelling of 668503490931 in words is "six hundred sixty-eight billion, five hundred three million, four hundred ninety thousand, nine hundred thirty-one".