90431147531 has 2 divisors, whose sum is σ = 90431147532. Its totient is φ = 90431147530.

The previous prime is 90431147519. The next prime is 90431147591. The reversal of 90431147531 is 13574113409.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90431147531 is a prime.

It is a super-2 number, since 2×90431147531² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (90431147591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45215573765 + 45215573766.

It is an arithmetic number, because the mean of its divisors is an integer number (45215573766).

Almost surely, 2^90431147531 is an apocalyptic number.

90431147531 is a deficient number, since it is larger than the sum of its proper divisors (1).

90431147531 is an equidigital number, since it uses as much as digits as its factorization.

90431147531 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 45360, while the sum is 38.

The spelling of 90431147531 in words is "ninety billion, four hundred thirty-one million, one hundred forty-seven thousand, five hundred thirty-one".