90185621 has 16 divisors (see below), whose sum is σ = 96215040. Its totient is φ = 84389760.

The previous prime is 90185617. The next prime is 90185657. The reversal of 90185621 is 12658109.

It is a cyclic number.

It is not a de Polignac number, because 90185621 - 2² = 90185617 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90185611) 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 15 ways as a sum of consecutive naturals, for example, 172841 + ... + 173361.

It is an arithmetic number, because the mean of its divisors is an integer number (6013440).

Almost surely, 2^90185621 is an apocalyptic number.

It is an amenable number.

90185621 is a deficient number, since it is larger than the sum of its proper divisors (6029419).

90185621 is a wasteful number, since it uses less digits than its factorization.

90185621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 724.

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 90185621 is about 9496.6110270980. The cubic root of 90185621 is about 448.4483530280.

The spelling of 90185621 in words is "ninety million, one hundred eighty-five thousand, six hundred twenty-one".