13218729925 has 6 divisors (see below), whose sum is σ = 16391225138. Its totient is φ = 10574983920.

The previous prime is 13218729911. The next prime is 13218729929. The reversal of 13218729925 is 52992781231.

It can be written as a sum of positive squares in 3 ways, for example, as 196953156 + 13021776769 = 14034^2 + 114113^2 .

It is not a de Polignac number, because 13218729925 - 2⁵ = 13218729893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13218729929) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 264374574 + ... + 264374623.

Almost surely, 2^13218729925 is an apocalyptic number.

It is an amenable number.

13218729925 is a deficient number, since it is larger than the sum of its proper divisors (3172495213).

13218729925 is an equidigital number, since it uses as much as digits as its factorization.

13218729925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 528749207 (or 528749202 counting only the distinct ones).

The product of its digits is 544320, while the sum is 49.

The spelling of 13218729925 in words is "thirteen billion, two hundred eighteen million, seven hundred twenty-nine thousand, nine hundred twenty-five".