90661756961 has 6 divisors (see below), whose sum is σ = 95684569362. Its totient is φ = 85890085200.

The previous prime is 90661756943. The next prime is 90661756973. The reversal of 90661756961 is 16965716609.

It can be written as a sum of positive squares in only one way, i.e., 87627840400 + 3033916561 = 296020^2 + 55081^2 .

It is not a de Polignac number, because 90661756961 - 2¹⁰ = 90661755937 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 90661756897 and 90661756906.

It is not an unprimeable number, because it can be changed into a prime (90661756931) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 125569940 + ... + 125570661.

It is an arithmetic number, because the mean of its divisors is an integer number (15947428227).

Almost surely, 2^90661756961 is an apocalyptic number.

It is an amenable number.

90661756961 is a deficient number, since it is larger than the sum of its proper divisors (5022812401).

90661756961 is a wasteful number, since it uses less digits than its factorization.

90661756961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 251140639 (or 251140620 counting only the distinct ones).

The product of its (nonzero) digits is 3674160, while the sum is 56.

The spelling of 90661756961 in words is "ninety billion, six hundred sixty-one million, seven hundred fifty-six thousand, nine hundred sixty-one".