668310631687 has 4 divisors (see below), whose sum is σ = 703484875480. Its totient is φ = 633136387896.

The previous prime is 668310631661. The next prime is 668310631699. The reversal of 668310631687 is 786136013866.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 668310631687 - 2⁷ = 668310631559 is a prime.

It is a super-4 number, since 4×668310631687⁴ (a number of 48 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668310631657) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17587121868 + ... + 17587121905.

It is an arithmetic number, because the mean of its divisors is an integer number (175871218870).

Almost surely, 2^668310631687 is an apocalyptic number.

668310631687 is a deficient number, since it is larger than the sum of its proper divisors (35174243793).

668310631687 is a wasteful number, since it uses less digits than its factorization.

668310631687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35174243792.

The product of its (nonzero) digits is 5225472, while the sum is 55.

The spelling of 668310631687 in words is "six hundred sixty-eight billion, three hundred ten million, six hundred thirty-one thousand, six hundred eighty-seven".