90800371561 has 3 divisors (see below), whose sum is σ = 90800672893. Its totient is φ = 90800070230.

The previous prime is 90800371531. The next prime is 90800371621. The reversal of 90800371561 is 16517300809.

The square root of 90800371561 is 301331.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 90800371561 - 2²⁷ = 90666153833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90800371511) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 150666 + ... + 451996.

Almost surely, 2^90800371561 is an apocalyptic number.

90800371561 is the 301331-st square number.

90800371561 is the 150666-th centered octagonal number.

It is an amenable number.

90800371561 is a deficient number, since it is larger than the sum of its proper divisors (301332).

90800371561 is an frugal number, since it uses more digits than its factorization.

90800371561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 602662 (or 301331 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 40.

The spelling of 90800371561 in words is "ninety billion, eight hundred million, three hundred seventy-one thousand, five hundred sixty-one".