87111640 has 64 divisors (see below), whose sum is σ = 244373760. Its totient is φ = 27150720.

The previous prime is 87111623. The next prime is 87111659. The reversal of 87111640 is 4611178.

87111640 = 113² + 114² + ... + 640².

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 87111599 and 87111608.

It is a congruent number.

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, 11062 + ... + 17221.

It is an arithmetic number, because the mean of its divisors is an integer number (3818340).

Almost surely, 2^87111640 is an apocalyptic number.

It is an amenable number.

87111640 is an abundant number, since it is smaller than the sum of its proper divisors (157262120).

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

87111640 is a wasteful number, since it uses less digits than its factorization.

87111640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28312 (or 28308 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 28.

The square root of 87111640 is about 9333.3616666237. The cubic root of 87111640 is about 443.2942145495.

The spelling of 87111640 in words is "eighty-seven million, one hundred eleven thousand, six hundred forty".