90691820 has 24 divisors (see below), whose sum is σ = 190922928. Its totient is φ = 36187200.

The previous prime is 90691819. The next prime is 90691823. The reversal of 90691820 is 2819609.

It is not an unprimeable number, because it can be changed into a prime (90691823) 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, 3035 + ... + 13805.

It is an arithmetic number, because the mean of its divisors is an integer number (7955122).

Almost surely, 2^90691820 is an apocalyptic number.

It is an amenable number.

90691820 is an abundant number, since it is smaller than the sum of its proper divisors (100231108).

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

90691820 is a wasteful number, since it uses less digits than its factorization.

90691820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11201 (or 11199 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 35.

The square root of 90691820 is about 9523.2252939852. The cubic root of 90691820 is about 449.2858136302.

The spelling of 90691820 in words is "ninety million, six hundred ninety-one thousand, eight hundred twenty".