63687865 has 16 divisors (see below), whose sum is σ = 81282960. Its totient is φ = 47738880.

The previous prime is 63687839. The next prime is 63687881. The reversal of 63687865 is 56878636.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 71289 + 63616576 = 267^2 + 7976^2 .

It is a de Polignac number, because none of the positive numbers 2^k-63687865 is a prime.

It is a super-2 number, since 2×63687865² = 8112288296516450, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18931 + ... + 22039.

It is an arithmetic number, because the mean of its divisors is an integer number (5080185).

Almost surely, 2^63687865 is an apocalyptic number.

It is an amenable number.

63687865 is a deficient number, since it is larger than the sum of its proper divisors (17595095).

63687865 is a wasteful number, since it uses less digits than its factorization.

63687865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3372.

The product of its digits is 1451520, while the sum is 49.

The square root of 63687865 is about 7980.4677181228. The cubic root of 63687865 is about 399.3486587120.

The spelling of 63687865 in words is "sixty-three million, six hundred eighty-seven thousand, eight hundred sixty-five".