90992813 has 4 divisors (see below), whose sum is σ = 91192380. Its totient is φ = 90793248.

The previous prime is 90992801. The next prime is 90992827. The reversal of 90992813 is 31829909.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31829909 = 313 ⋅101693.

It can be written as a sum of positive squares in 2 ways, for example, as 68591524 + 22401289 = 8282^2 + 4733^2 .

It is a cyclic number.

It is not a de Polignac number, because 90992813 - 2¹⁸ = 90730669 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90995813) 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, 99098 + ... + 100011.

It is an arithmetic number, because the mean of its divisors is an integer number (22798095).

Almost surely, 2^90992813 is an apocalyptic number.

It is an amenable number.

90992813 is a deficient number, since it is larger than the sum of its proper divisors (199567).

90992813 is a wasteful number, since it uses less digits than its factorization.

90992813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199566.

The product of its (nonzero) digits is 34992, while the sum is 41.

The square root of 90992813 is about 9539.0153055753. The cubic root of 90992813 is about 449.7823029319.

The spelling of 90992813 in words is "ninety million, nine hundred ninety-two thousand, eight hundred thirteen".