90688978931 has 2 divisors, whose sum is σ = 90688978932. Its totient is φ = 90688978930.

The previous prime is 90688978879. The next prime is 90688978951. The reversal of 90688978931 is 13987988609.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 90688978931 - 2¹⁴ = 90688962547 is a prime.

It is a super-2 number, since 2×90688978931² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (90688978951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45344489465 + 45344489466.

It is an arithmetic number, because the mean of its divisors is an integer number (45344489466).

Almost surely, 2^90688978931 is an apocalyptic number.

90688978931 is a deficient number, since it is larger than the sum of its proper divisors (1).

90688978931 is an equidigital number, since it uses as much as digits as its factorization.

90688978931 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 47029248, while the sum is 68.

The spelling of 90688978931 in words is "ninety billion, six hundred eighty-eight million, nine hundred seventy-eight thousand, nine hundred thirty-one".