87865644825 has 54 divisors (see below), whose sum is σ = 183071381454. Its totient is φ = 40167146880.

The previous prime is 87865644793. The next prime is 87865644847. The reversal of 87865644825 is 52844656878.

87865644825 is a `hidden beast` number, since 8 + 7 + 8 + 6 + 564 + 48 + 25 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 885479049 + 86980165776 = 29757^2 + 294924^2 .

It is not a de Polignac number, because 87865644825 - 2⁵ = 87865644793 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 3973812 + ... + 3995861.

Almost surely, 2^87865644825 is an apocalyptic number.

It is an amenable number.

87865644825 is an abundant number, since it is smaller than the sum of its proper divisors (95205736629).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

87865644825 is a wasteful number, since it uses less digits than its factorization.

87865644825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7969703 (or 7969688 counting only the distinct ones).

The product of its digits is 103219200, while the sum is 63.

The spelling of 87865644825 in words is "eighty-seven billion, eight hundred sixty-five million, six hundred forty-four thousand, eight hundred twenty-five".