90565813 has 8 divisors (see below), whose sum is σ = 97788600. Its totient is φ = 83379648.

The previous prime is 90565801. The next prime is 90565823. The reversal of 90565813 is 31856509.

It can be written as a sum of positive squares in 4 ways, for example, as 68644 + 90497169 = 262^2 + 9513^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 90565813 - 2⁵ = 90565781 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90565823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3898 + ... + 14011.

It is an arithmetic number, because the mean of its divisors is an integer number (12223575).

Almost surely, 2^90565813 is an apocalyptic number.

It is an amenable number.

90565813 is a deficient number, since it is larger than the sum of its proper divisors (7222787).

90565813 is a wasteful number, since it uses less digits than its factorization.

90565813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18311.

The product of its (nonzero) digits is 32400, while the sum is 37.

The square root of 90565813 is about 9516.6072210636. The cubic root of 90565813 is about 449.0776383057.

It can be divided in two parts, 90565 and 813, that added together give a triangular number (91378 = T₄₂₇).

The spelling of 90565813 in words is "ninety million, five hundred sixty-five thousand, eight hundred thirteen".