90431491 has 2 divisors, whose sum is σ = 90431492. Its totient is φ = 90431490.

The previous prime is 90431477. The next prime is 90431503. The reversal of 90431491 is 19413409.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 90431491 - 2²⁵ = 56877059 is a prime.

It is not a weakly prime, because it can be changed into another prime (90431291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45215745 + 45215746.

It is an arithmetic number, because the mean of its divisors is an integer number (45215746).

Almost surely, 2^90431491 is an apocalyptic number.

90431491 is a deficient number, since it is larger than the sum of its proper divisors (1).

90431491 is an equidigital number, since it uses as much as digits as its factorization.

90431491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 90431491 is about 9509.5473604163. The cubic root of 90431491 is about 448.8555130884.

The spelling of 90431491 in words is "ninety million, four hundred thirty-one thousand, four hundred ninety-one".