89817521 has 4 divisors (see below), whose sum is σ = 91047972. Its totient is φ = 88587072.

The previous prime is 89817493. The next prime is 89817523. The reversal of 89817521 is 12571898.

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 58736896 + 31080625 = 7664^2 + 5575^2 .

It is a cyclic number.

It is not a de Polignac number, because 89817521 - 2¹⁰ = 89816497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (89817523) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 615116 + ... + 615261.

It is an arithmetic number, because the mean of its divisors is an integer number (22761993).

Almost surely, 2^89817521 is an apocalyptic number.

It is an amenable number.

89817521 is a deficient number, since it is larger than the sum of its proper divisors (1230451).

89817521 is a wasteful number, since it uses less digits than its factorization.

89817521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1230450.

The product of its digits is 40320, while the sum is 41.

The square root of 89817521 is about 9477.2106128333. The cubic root of 89817521 is about 447.8373948175.

The spelling of 89817521 in words is "eighty-nine million, eight hundred seventeen thousand, five hundred twenty-one".