90661756973 has 2 divisors, whose sum is σ = 90661756974. Its totient is φ = 90661756972.

The previous prime is 90661756943. The next prime is 90661756981. The reversal of 90661756973 is 37965716609.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 87892682089 + 2769074884 = 296467^2 + 52622^2 .

It is a cyclic number.

It is not a de Polignac number, because 90661756973 - 2¹² = 90661752877 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90661756943) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45330878486 + 45330878487.

It is an arithmetic number, because the mean of its divisors is an integer number (45330878487).

Almost surely, 2^90661756973 is an apocalyptic number.

It is an amenable number.

90661756973 is a deficient number, since it is larger than the sum of its proper divisors (1).

90661756973 is an equidigital number, since it uses as much as digits as its factorization.

90661756973 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12859560, while the sum is 59.

The spelling of 90661756973 in words is "ninety billion, six hundred sixty-one million, seven hundred fifty-six thousand, nine hundred seventy-three".