16115206640625 has 81 divisors (see below), whose sum is σ = 29110482654019. Its totient is φ = 8590762500000.

The previous prime is 16115206640591. The next prime is 16115206640653. The reversal of 16115206640625 is 52604660251161.

The square root of 16115206640625 is 4014375.

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

16115206640625 is a `hidden beast` number, since 1 + 6 + 1 + 1 + 520 + 6 + 64 + 0 + 62 + 5 = 666.

It can be written as a sum of positive squares in 13 ways, for example, as 8078049680481 + 8037156960144 = 2842191^2 + 2834988^2 .

It is not a de Polignac number, because 16115206640625 - 2²³ = 16115198252017 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 7526952055 + ... + 7526954195.

Almost surely, 2^{16115206640625} is an apocalyptic number.

16115206640625 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

16115206640625 is the 4014375-th square number.

16115206640625 is the 2007188-th centered octagonal number.

It is an amenable number.

16115206640625 is a deficient number, since it is larger than the sum of its proper divisors (12995276013394).

16115206640625 is an frugal number, since it uses more digits than its factorization.

16115206640625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4328 (or 2149 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 45.

Adding to 16115206640625 its reverse (52604660251161), we get a palindrome (68719866891786).

The spelling of 16115206640625 in words is "sixteen trillion, one hundred fifteen billion, two hundred six million, six hundred forty thousand, six hundred twenty-five".