21612145425 has 48 divisors (see below), whose sum is σ = 38497327680. Its totient is φ = 10635229440.

The previous prime is 21612145417. The next prime is 21612145433. The reversal of 21612145425 is 52454121612.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21612145417) and next prime (21612145433).

It is not a de Polignac number, because 21612145425 - 2³ = 21612145417 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3816246 + ... + 3821904.

It is an arithmetic number, because the mean of its divisors is an integer number (802027660).

Almost surely, 2^21612145425 is an apocalyptic number.

21612145425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21612145425 is a deficient number, since it is larger than the sum of its proper divisors (16885182255).

21612145425 is a wasteful number, since it uses less digits than its factorization.

21612145425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9602 (or 9597 counting only the distinct ones).

The product of its digits is 19200, while the sum is 33.

The spelling of 21612145425 in words is "twenty-one billion, six hundred twelve million, one hundred forty-five thousand, four hundred twenty-five".