86721588 has 18 divisors (see below), whose sum is σ = 219212994. Its totient is φ = 28907184.

The previous prime is 86721587. The next prime is 86721611. The reversal of 86721588 is 88512768.

86721588 is a `hidden beast` number, since 8 + 67 + 2 + 1 + 588 = 666.

It can be written as a sum of positive squares in only one way, i.e., 64931364 + 21790224 = 8058^2 + 4668^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (86721581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1204431 + ... + 1204502.

Almost surely, 2^86721588 is an apocalyptic number.

It is an amenable number.

86721588 is an abundant number, since it is smaller than the sum of its proper divisors (132491406).

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

86721588 is a wasteful number, since it uses less digits than its factorization.

86721588 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2408943 (or 2408938 counting only the distinct ones).

The product of its digits is 215040, while the sum is 45.

The square root of 86721588 is about 9312.4426441187. The cubic root of 86721588 is about 442.6315916206.

The spelling of 86721588 in words is "eighty-six million, seven hundred twenty-one thousand, five hundred eighty-eight".