99357974521 has 9 divisors (see below), whose sum is σ = 107593250031. Its totient is φ = 91711270872.

The previous prime is 99357974509. The next prime is 99357974549. The reversal of 99357974521 is 12547975399.

The square root of 99357974521 is 315211.

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., 14697925225 + 84660049296 = 121235^2 + 290964^2 .

It is not a de Polignac number, because 99357974521 - 2¹⁷ = 99357843449 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 99357974521.

It is not an unprimeable number, because it can be changed into a prime (99357974621) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 4085620 + ... + 4109866.

It is an arithmetic number, because the mean of its divisors is an integer number (11954805559).

Almost surely, 2^99357974521 is an apocalyptic number.

99357974521 is the 315211-st square number.

99357974521 is the 157606-th centered octagonal number.

It is an amenable number.

99357974521 is a deficient number, since it is larger than the sum of its proper divisors (8235275510).

99357974521 is an frugal number, since it uses more digits than its factorization.

99357974521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48520 (or 24260 counting only the distinct ones).

The product of its digits is 21432600, while the sum is 61.

The spelling of 99357974521 in words is "ninety-nine billion, three hundred fifty-seven million, nine hundred seventy-four thousand, five hundred twenty-one".