86720931 has 12 divisors (see below), whose sum is σ = 136651320. Its totient is φ = 52558080.

The previous prime is 86720903. The next prime is 86720939. The reversal of 86720931 is 13902768.

It is not a de Polignac number, because 86720931 - 2⁶ = 86720867 is a prime.

It is a super-2 number, since 2×86720931² = 15041039747013522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (86720939) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 437886 + ... + 438083.

It is an arithmetic number, because the mean of its divisors is an integer number (11387610).

Almost surely, 2^86720931 is an apocalyptic number.

86720931 is a deficient number, since it is larger than the sum of its proper divisors (49930389).

86720931 is a wasteful number, since it uses less digits than its factorization.

86720931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 875986 (or 875983 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 86720931 is about 9312.4073686668. The cubic root of 86720931 is about 442.6304738301.

The spelling of 86720931 in words is "eighty-six million, seven hundred twenty thousand, nine hundred thirty-one".