19907799025 has 9 divisors (see below), whose sum is σ = 24686545611. Its totient is φ = 15925674840.

The previous prime is 19907799011. The next prime is 19907799047. The reversal of 19907799025 is 52099770991.

The square root of 19907799025 is 141095.

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., 7166807649 + 12740991376 = 84657^2 + 112876^2 .

It is a de Polignac number, because none of the positive numbers 2^k-19907799025 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 691366 + ... + 719584.

Almost surely, 2^19907799025 is an apocalyptic number.

19907799025 is the 141095-th square number.

19907799025 is the 70548-th centered octagonal number.

It is an amenable number.

19907799025 is a deficient number, since it is larger than the sum of its proper divisors (4778746586).

19907799025 is an frugal number, since it uses more digits than its factorization.

19907799025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56448 (or 28224 counting only the distinct ones).

The product of its (nonzero) digits is 3214890, while the sum is 58.

The spelling of 19907799025 in words is "nineteen billion, nine hundred seven million, seven hundred ninety-nine thousand, twenty-five".