90431278561 has 16 divisors (see below), whose sum is σ = 97911031680. Its totient is φ = 83027162880.

The previous prime is 90431278559. The next prime is 90431278621. The reversal of 90431278561 is 16587213409.

It is a cyclic number.

It is not a de Polignac number, because 90431278561 - 2¹ = 90431278559 is a prime.

It is a super-2 number, since 2×90431278561² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90431278661) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2611386 + ... + 2645788.

It is an arithmetic number, because the mean of its divisors is an integer number (6119439480).

It is a 1-persistent number, because it is pandigital, but 2⋅90431278561 = 180862557122 is not.

Almost surely, 2^90431278561 is an apocalyptic number.

It is an amenable number.

90431278561 is a deficient number, since it is larger than the sum of its proper divisors (7479753119).

90431278561 is a wasteful number, since it uses less digits than its factorization.

90431278561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35496.

The product of its (nonzero) digits is 362880, while the sum is 46.

The spelling of 90431278561 in words is "ninety billion, four hundred thirty-one million, two hundred seventy-eight thousand, five hundred sixty-one".