687115731 has 8 divisors (see below), whose sum is σ = 955987200. Its totient is φ = 438160712.

The previous prime is 687115727. The next prime is 687115733. The reversal of 687115731 is 137511786.

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 687115731 - 2² = 687115727 is a prime.

It is a super-2 number, since 2×687115731² = 944256055575328722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 687115731.

It is not an unprimeable number, because it can be changed into a prime (687115733) 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, 4979031 + ... + 4979168.

It is an arithmetic number, because the mean of its divisors is an integer number (119498400).

Almost surely, 2^687115731 is an apocalyptic number.

687115731 is a deficient number, since it is larger than the sum of its proper divisors (268871469).

687115731 is a wasteful number, since it uses less digits than its factorization.

687115731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9958225.

The product of its digits is 35280, while the sum is 39.

The square root of 687115731 is about 26212.8924577201. The cubic root of 687115731 is about 882.4226164067.

The spelling of 687115731 in words is "six hundred eighty-seven million, one hundred fifteen thousand, seven hundred thirty-one".