90174521 has 4 divisors (see below), whose sum is σ = 90241572. Its totient is φ = 90107472.

The previous prime is 90174509. The next prime is 90174523. The reversal of 90174521 is 12547109.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 58308496 + 31866025 = 7636^2 + 5645^2 .

It is a cyclic number.

It is not a de Polignac number, because 90174521 - 2¹⁸ = 89912377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90174523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31466 + ... + 34211.

It is an arithmetic number, because the mean of its divisors is an integer number (22560393).

Almost surely, 2^90174521 is an apocalyptic number.

It is an amenable number.

90174521 is a deficient number, since it is larger than the sum of its proper divisors (67051).

90174521 is a wasteful number, since it uses less digits than its factorization.

90174521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67050.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 90174521 is about 9496.0265901060. The cubic root of 90174521 is about 448.4299540087.

The spelling of 90174521 in words is "ninety million, one hundred seventy-four thousand, five hundred twenty-one".