90991718 has 16 divisors (see below), whose sum is σ = 147593664. Its totient is φ = 41907840.

The previous prime is 90991709. The next prime is 90991721. The reversal of 90991718 is 81719909.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26873 + ... + 30068.

It is an arithmetic number, because the mean of its divisors is an integer number (9224604).

Almost surely, 2^90991718 is an apocalyptic number.

90991718 is a deficient number, since it is larger than the sum of its proper divisors (56601946).

90991718 is a wasteful number, since it uses less digits than its factorization.

90991718 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57007.

The product of its (nonzero) digits is 40824, while the sum is 44.

The square root of 90991718 is about 9538.9579095413. The cubic root of 90991718 is about 449.7804987102.

The spelling of 90991718 in words is "ninety million, nine hundred ninety-one thousand, seven hundred eighteen".