97944587521 has 27 divisors (see below), whose sum is σ = 112633453443. Its totient is φ = 85100355120.

The previous prime is 97944587519. The next prime is 97944587537. The reversal of 97944587521 is 12578544979.

The square root of 97944587521 is 312961.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 73970400625 + 23974186896 = 271975^2 + 154836^2 .

It is not a de Polignac number, because 97944587521 - 2¹ = 97944587519 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 97944587521.

It is not an unprimeable number, because it can be changed into a prime (97944587551) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 79178515 + ... + 79179751.

Almost surely, 2^97944587521 is an apocalyptic number.

97944587521 is the 312961-st square number.

97944587521 is the 156481-st centered octagonal number.

It is an amenable number.

97944587521 is a deficient number, since it is larger than the sum of its proper divisors (14688865922).

97944587521 is an equidigital number, since it uses as much as digits as its factorization.

97944587521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2542 (or 1271 counting only the distinct ones).

The product of its digits is 25401600, while the sum is 61.

The spelling of 97944587521 in words is "ninety-seven billion, nine hundred forty-four million, five hundred eighty-seven thousand, five hundred twenty-one".