90491631 has 4 divisors (see below), whose sum is σ = 120655512. Its totient is φ = 60327752.

The previous prime is 90491593. The next prime is 90491647. The reversal of 90491631 is 13619409.

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 90491631 - 2⁶ = 90491567 is a prime.

It is a super-2 number, since 2×90491631² = 16377470562080322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 90491592 and 90491601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90491831) 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, 15081936 + ... + 15081941.

It is an arithmetic number, because the mean of its divisors is an integer number (30163878).

Almost surely, 2^90491631 is an apocalyptic number.

90491631 is a deficient number, since it is larger than the sum of its proper divisors (30163881).

90491631 is a wasteful number, since it uses less digits than its factorization.

90491631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30163880.

The product of its (nonzero) digits is 5832, while the sum is 33.

The square root of 90491631 is about 9512.7089201762. The cubic root of 90491631 is about 448.9549924050.

The spelling of 90491631 in words is "ninety million, four hundred ninety-one thousand, six hundred thirty-one".