90509812 has 12 divisors (see below), whose sum is σ = 163854180. Its totient is φ = 43694336.

The previous prime is 90509803. The next prime is 90509813. The reversal of 90509812 is 21890509.

It can be written as a sum of positive squares in 2 ways, for example, as 73170916 + 17338896 = 8554^2 + 4164^2 .

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90509813) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 390013 + ... + 390244.

It is an arithmetic number, because the mean of its divisors is an integer number (13654515).

Almost surely, 2^90509812 is an apocalyptic number.

It is an amenable number.

90509812 is a deficient number, since it is larger than the sum of its proper divisors (73344368).

90509812 is a wasteful number, since it uses less digits than its factorization.

90509812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 780290 (or 780288 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 34.

The square root of 90509812 is about 9513.6644885134. The cubic root of 90509812 is about 448.9850574472.

The spelling of 90509812 in words is "ninety million, five hundred nine thousand, eight hundred twelve".