90991860 has 24 divisors (see below), whose sum is σ = 254777376. Its totient is φ = 24264480.

The previous prime is 90991853. The next prime is 90991861. The reversal of 90991860 is 6819909.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90991861) 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, 758206 + ... + 758325.

It is an arithmetic number, because the mean of its divisors is an integer number (10615724).

Almost surely, 2^90991860 is an apocalyptic number.

It is an amenable number.

90991860 is an abundant number, since it is smaller than the sum of its proper divisors (163785516).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

90991860 is a wasteful number, since it uses less digits than its factorization.

90991860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1516543 (or 1516541 counting only the distinct ones).

The product of its (nonzero) digits is 34992, while the sum is 42.

The square root of 90991860 is about 9538.9653526994. The cubic root of 90991860 is about 449.7807326832.

The spelling of 90991860 in words is "ninety million, nine hundred ninety-one thousand, eight hundred sixty".