86920991 has 4 divisors (see below), whose sum is σ = 91495800. Its totient is φ = 82346184.

The previous prime is 86920987. The next prime is 86921041. The reversal of 86920991 is 19902968.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 86920991 - 2² = 86920987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (86920961) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2287376 + ... + 2287413.

It is an arithmetic number, because the mean of its divisors is an integer number (22873950).

Almost surely, 2^86920991 is an apocalyptic number.

86920991 is a deficient number, since it is larger than the sum of its proper divisors (4574809).

86920991 is a wasteful number, since it uses less digits than its factorization.

86920991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4574808.

The product of its (nonzero) digits is 69984, while the sum is 44.

The square root of 86920991 is about 9323.1427641113. The cubic root of 86920991 is about 442.9705864323.

The spelling of 86920991 in words is "eighty-six million, nine hundred twenty thousand, nine hundred ninety-one".