90818531 has 4 divisors (see below), whose sum is σ = 91110864. Its totient is φ = 90526200.

The previous prime is 90818527. The next prime is 90818549. The reversal of 90818531 is 13581809.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13581809 = 113 ⋅120193.

It is a cyclic number.

It is not a de Polignac number, because 90818531 - 2² = 90818527 is a prime.

It is a super-2 number, since 2×90818531² = 16496011145995922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 90818491 and 90818500.

It is not an unprimeable number, because it can be changed into a prime (90818551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 145700 + ... + 146321.

It is an arithmetic number, because the mean of its divisors is an integer number (22777716).

Almost surely, 2^90818531 is an apocalyptic number.

90818531 is a deficient number, since it is larger than the sum of its proper divisors (292333).

90818531 is a wasteful number, since it uses less digits than its factorization.

90818531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 292332.

The product of its (nonzero) digits is 8640, while the sum is 35.

The square root of 90818531 is about 9529.8757074791. The cubic root of 90818531 is about 449.4949576747.

The spelling of 90818531 in words is "ninety million, eight hundred eighteen thousand, five hundred thirty-one".