86525721 has 12 divisors (see below), whose sum is σ = 128359972. Its totient is φ = 56124576.

The previous prime is 86525713. The next prime is 86525771. The reversal of 86525721 is 12752568.

It is a happy number.

86525721 is a `hidden beast` number, since 86 + 5 + 2 + 572 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 76317696 + 10208025 = 8736^2 + 3195^2 .

It is not a de Polignac number, because 86525721 - 2³ = 86525713 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (86525771) 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 11 ways as a sum of consecutive naturals, for example, 129586 + ... + 130251.

Almost surely, 2^86525721 is an apocalyptic number.

It is an amenable number.

86525721 is a deficient number, since it is larger than the sum of its proper divisors (41834251).

86525721 is a wasteful number, since it uses less digits than its factorization.

86525721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259880 (or 259877 counting only the distinct ones).

The product of its digits is 33600, while the sum is 36.

The square root of 86525721 is about 9301.9202856184. The cubic root of 86525721 is about 442.2981019001.

The spelling of 86525721 in words is "eighty-six million, five hundred twenty-five thousand, seven hundred twenty-one".