90951099561 has 45 divisors (see below), whose sum is σ = 158080322829. Its totient is φ = 51961199976.

The previous prime is 90951099521. The next prime is 90951099571. The reversal of 90951099561 is 16599015909.

The square root of 90951099561 is 301581.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 90951099561 - 2²⁵ = 90917545129 is a prime.

It is a super-2 number, since 2×90951099561² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 90951099498 and 90951099507.

It is not an unprimeable number, because it can be changed into a prime (90951099521) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 18997210 + ... + 19001996.

Almost surely, 2^90951099561 is an apocalyptic number.

90951099561 is the 301581-st square number.

90951099561 is the 150791-st centered octagonal number.

It is an amenable number.

90951099561 is a deficient number, since it is larger than the sum of its proper divisors (67129223268).

90951099561 is an frugal number, since it uses more digits than its factorization.

90951099561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9600 (or 4797 counting only the distinct ones).

The product of its (nonzero) digits is 984150, while the sum is 54.

The spelling of 90951099561 in words is "ninety billion, nine hundred fifty-one million, ninety-nine thousand, five hundred sixty-one".