87639651 has 32 divisors (see below), whose sum is σ = 143427840. Its totient is φ = 53100360.

The previous prime is 87639649. The next prime is 87639659. The reversal of 87639651 is 15693678.

It is a happy number.

87639651 is a `hidden beast` number, since 8 + 7 + 639 + 6 + 5 + 1 = 666.

It is not a de Polignac number, because 87639651 - 2¹ = 87639649 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 87639597 and 87639606.

It is not an unprimeable number, because it can be changed into a prime (87639659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22236 + ... + 25878.

It is an arithmetic number, because the mean of its divisors is an integer number (4482120).

Almost surely, 2^87639651 is an apocalyptic number.

87639651 is a gapful number since it is divisible by the number (81) formed by its first and last digit.

87639651 is a deficient number, since it is larger than the sum of its proper divisors (55788189).

87639651 is an equidigital number, since it uses as much as digits as its factorization.

87639651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3675 (or 3657 counting only the distinct ones).

The product of its digits is 272160, while the sum is 45.

The square root of 87639651 is about 9361.6051508275. The cubic root of 87639651 is about 444.1880594874.

The spelling of 87639651 in words is "eighty-seven million, six hundred thirty-nine thousand, six hundred fifty-one".