128915927433225 has 81 divisors (see below), whose sum is σ = 243701263301223. Its totient is φ = 65134833605280.

The previous prime is 128915927433217. The next prime is 128915927433229. The reversal of 128915927433225 is 522334729519821.

The square root of 128915927433225 is 11354115.

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

128915927433225 is a `hidden beast` number, since 1 + 2 + 8 + 9 + 1 + 5 + 9 + 274 + 332 + 25 = 666.

It can be written as a sum of positive squares in only one way, i.e., 46409733875961 + 82506193557264 = 6812469^2 + 9083292^2 .

It is not a de Polignac number, because 128915927433225 - 2³ = 128915927433217 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128915927433229) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 3235902856 + ... + 3235942694.

Almost surely, 2^{128915927433225} is an apocalyptic number.

128915927433225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

128915927433225 is the 11354115-th square number.

128915927433225 is the 5677058-th centered octagonal number.

It is an amenable number.

128915927433225 is a deficient number, since it is larger than the sum of its proper divisors (114785335867998).

128915927433225 is an frugal number, since it uses more digits than its factorization.

128915927433225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79732 (or 39866 counting only the distinct ones).

The product of its digits is 65318400, while the sum is 63.

The spelling of 128915927433225 in words is "one hundred twenty-eight trillion, nine hundred fifteen billion, nine hundred twenty-seven million, four hundred thirty-three thousand, two hundred twenty-five".