90138431 has 2 divisors, whose sum is σ = 90138432. Its totient is φ = 90138430.

The previous prime is 90138407. The next prime is 90138457. The reversal of 90138431 is 13483109.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90138431 is a prime.

It is a super-2 number, since 2×90138431² = 16249873486283522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 90138394 and 90138403.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90138491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45069215 + 45069216.

It is an arithmetic number, because the mean of its divisors is an integer number (45069216).

Almost surely, 2^90138431 is an apocalyptic number.

90138431 is a deficient number, since it is larger than the sum of its proper divisors (1).

90138431 is an equidigital number, since it uses as much as digits as its factorization.

90138431 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 90138431 is about 9494.1261314562. The cubic root of 90138431 is about 448.3701218950.

The spelling of 90138431 in words is "ninety million, one hundred thirty-eight thousand, four hundred thirty-one".