90913815 has 24 divisors (see below), whose sum is σ = 160561440. Its totient is φ = 47571264.

The previous prime is 90913813. The next prime is 90913829. The reversal of 90913815 is 51831909.

It is a happy number.

It is not a de Polignac number, because 90913815 - 2¹ = 90913813 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 90913815.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90913813) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16675 + ... + 21444.

It is an arithmetic number, because the mean of its divisors is an integer number (6690060).

Almost surely, 2^90913815 is an apocalyptic number.

90913815 is a deficient number, since it is larger than the sum of its proper divisors (69647625).

90913815 is a wasteful number, since it uses less digits than its factorization.

90913815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38183 (or 38180 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 36.

The square root of 90913815 is about 9534.8736226549. The cubic root of 90913815 is about 449.6521014766.

The spelling of 90913815 in words is "ninety million, nine hundred thirteen thousand, eight hundred fifteen".