90985820 has 12 divisors (see below), whose sum is σ = 191070264. Its totient is φ = 36394320.

The previous prime is 90985781. The next prime is 90985841. The reversal of 90985820 is 2858909.

It is a happy number.

It is a hoax number, since the sum of its digits (41) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2274626 + ... + 2274665.

It is an arithmetic number, because the mean of its divisors is an integer number (15922522).

Almost surely, 2^90985820 is an apocalyptic number.

It is an amenable number.

90985820 is an abundant number, since it is smaller than the sum of its proper divisors (100084444).

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

90985820 is a wasteful number, since it uses less digits than its factorization.

90985820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4549300 (or 4549298 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 41.

The square root of 90985820 is about 9538.6487512645. The cubic root of 90985820 is about 449.7707803800.

The spelling of 90985820 in words is "ninety million, nine hundred eighty-five thousand, eight hundred twenty".