87972390 has 48 divisors (see below), whose sum is σ = 249524496. Its totient is φ = 21326400.

The previous prime is 87972377. The next prime is 87972397. The reversal of 87972390 is 9327978.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87972397) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 43441 + ... + 45420.

It is an arithmetic number, because the mean of its divisors is an integer number (5198427).

Almost surely, 2^87972390 is an apocalyptic number.

87972390 is an abundant number, since it is smaller than the sum of its proper divisors (161552106).

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

87972390 is a wasteful number, since it uses less digits than its factorization.

87972390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88885 (or 88882 counting only the distinct ones).

The product of its (nonzero) digits is 190512, while the sum is 45.

The square root of 87972390 is about 9379.3597862541. The cubic root of 87972390 is about 444.7494949978.

The spelling of 87972390 in words is "eighty-seven million, nine hundred seventy-two thousand, three hundred ninety".