656719538687 has 8 divisors (see below), whose sum is σ = 665658147840. Its totient is φ = 647796572280.

The previous prime is 656719538681. The next prime is 656719538707. The reversal of 656719538687 is 786835917656.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 656719538687 - 2¹² = 656719534591 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 656719538687.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (656719538681) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3826139 + ... + 3994092.

It is an arithmetic number, because the mean of its divisors is an integer number (83207268480).

Almost surely, 2^656719538687 is an apocalyptic number.

656719538687 is a deficient number, since it is larger than the sum of its proper divisors (8938609153).

656719538687 is a wasteful number, since it uses less digits than its factorization.

656719538687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7821373.

The product of its digits is 457228800, while the sum is 71.

The spelling of 656719538687 in words is "six hundred fifty-six billion, seven hundred nineteen million, five hundred thirty-eight thousand, six hundred eighty-seven".