87047921864 has 16 divisors (see below), whose sum is σ = 172815727500. Its totient is φ = 40963727872.

The previous prime is 87047921861. The next prime is 87047921897. The reversal of 87047921864 is 46812974078.

It can be written as a sum of positive squares in 2 ways, for example, as 84996737764 + 2051184100 = 291542^2 + 45290^2 .

It is not an unprimeable number, because it can be changed into a prime (87047921861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 320028989 + ... + 320029260.

Almost surely, 2^87047921864 is an apocalyptic number.

It is an amenable number.

87047921864 is a deficient number, since it is larger than the sum of its proper divisors (85767805636).

87047921864 is a wasteful number, since it uses less digits than its factorization.

87047921864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 640058272 (or 640058268 counting only the distinct ones).

The product of its (nonzero) digits is 5419008, while the sum is 56.

The spelling of 87047921864 in words is "eighty-seven billion, forty-seven million, nine hundred twenty-one thousand, eight hundred sixty-four".