87221590 has 32 divisors (see below), whose sum is σ = 165784320. Its totient is φ = 32948064.

The previous prime is 87221581. The next prime is 87221591. The reversal of 87221590 is 9512278.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87221591) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 88239 + ... + 89221.

It is an arithmetic number, because the mean of its divisors is an integer number (5180760).

Almost surely, 2^87221590 is an apocalyptic number.

87221590 is the 4670-th decagonal number.

87221590 is a deficient number, since it is larger than the sum of its proper divisors (78562730).

87221590 is a wasteful number, since it uses less digits than its factorization.

87221590 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1476.

The product of its (nonzero) digits is 10080, while the sum is 34.

The square root of 87221590 is about 9339.2499698852. The cubic root of 87221590 is about 443.4806408681.

The spelling of 87221590 in words is "eighty-seven million, two hundred twenty-one thousand, five hundred ninety".