90657991 has 8 divisors (see below), whose sum is σ = 96137280. Its totient is φ = 85195008.

The previous prime is 90657989. The next prime is 90658027. The reversal of 90657991 is 19975609.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 90657991 - 2¹ = 90657989 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 (90657961) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8515 + ... + 15931.

It is an arithmetic number, because the mean of its divisors is an integer number (12017160).

Almost surely, 2^90657991 is an apocalyptic number.

90657991 is a deficient number, since it is larger than the sum of its proper divisors (5479289).

90657991 is a wasteful number, since it uses less digits than its factorization.

90657991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8153.

The product of its (nonzero) digits is 153090, while the sum is 46.

The square root of 90657991 is about 9521.4489968702. The cubic root of 90657991 is about 449.2299439095.

The spelling of 90657991 in words is "ninety million, six hundred fifty-seven thousand, nine hundred ninety-one".