90656991 has 6 divisors (see below), whose sum is σ = 130949000. Its totient is φ = 60437988.

The previous prime is 90656983. The next prime is 90657001. The reversal of 90656991 is 19965609.

It is not a de Polignac number, because 90656991 - 2³ = 90656983 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 (90656921) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5036491 + ... + 5036508.

Almost surely, 2^90656991 is an apocalyptic number.

90656991 is a deficient number, since it is larger than the sum of its proper divisors (40292009).

90656991 is a wasteful number, since it uses less digits than its factorization.

90656991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10073005 (or 10073002 counting only the distinct ones).

The product of its (nonzero) digits is 131220, while the sum is 45.

The square root of 90656991 is about 9521.3964837097. The cubic root of 90656991 is about 449.2282921647.

The spelling of 90656991 in words is "ninety million, six hundred fifty-six thousand, nine hundred ninety-one".