15642423225 has 216 divisors, whose sum is σ = 33482223320. Its totient is φ = 6934118400.

The previous prime is 15642423193. The next prime is 15642423239. The reversal of 15642423225 is 52232424651.

15642423225 is a `hidden beast` number, since 1 + 5 + 6 + 4 + 2 + 423 + 225 = 666.

It can be written as a sum of positive squares in 12 ways, for example, as 5062037904 + 10580385321 = 71148^2 + 102861^2 .

It is not a de Polignac number, because 15642423225 - 2⁵ = 15642423193 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 15642423225.

It is an unprimeable number.

It is a polite number, since it can be written in 215 ways as a sum of consecutive naturals, for example, 68307411 + ... + 68307639.

Almost surely, 2^15642423225 is an apocalyptic number.

15642423225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

15642423225 is an abundant number, since it is smaller than the sum of its proper divisors (17839800095).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

15642423225 is a wasteful number, since it uses less digits than its factorization.

15642423225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 473 (or 454 counting only the distinct ones).

The product of its digits is 115200, while the sum is 36.

Adding to 15642423225 its reverse (52232424651), we get a palindrome (67874847876).

The spelling of 15642423225 in words is "fifteen billion, six hundred forty-two million, four hundred twenty-three thousand, two hundred twenty-five".