99644392225 has 81 divisors (see below), whose sum is σ = 149339317881. Its totient is φ = 65759332800.

The previous prime is 99644392147. The next prime is 99644392273. The reversal of 99644392225 is 52229344699.

The square root of 99644392225 is 315665.

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

It can be written as a sum of positive squares in 4 ways, for example, as 1369666081 + 98274726144 = 37009^2 + 313488^2 .

It is not a de Polignac number, because 99644392225 - 2¹⁹ = 99643867937 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 320399820 + ... + 320400130.

Almost surely, 2^99644392225 is an apocalyptic number.

99644392225 is the 315665-th square number.

99644392225 is the 157833-rd centered octagonal number.

It is an amenable number.

99644392225 is a deficient number, since it is larger than the sum of its proper divisors (49694925656).

99644392225 is an equidigital number, since it uses as much as digits as its factorization.

99644392225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 704 (or 352 counting only the distinct ones).

The product of its digits is 8398080, while the sum is 55.

The spelling of 99644392225 in words is "ninety-nine billion, six hundred forty-four million, three hundred ninety-two thousand, two hundred twenty-five".