21252415425 has 48 divisors (see below), whose sum is σ = 35450022720. Its totient is φ = 11234039040.

The previous prime is 21252415421. The next prime is 21252415427. The reversal of 21252415425 is 52451425212.

It is not a de Polignac number, because 21252415425 - 2² = 21252415421 is a prime.

It is a super-2 number, since 2×21252415425² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21252415421) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7890379 + ... + 7893071.

It is an arithmetic number, because the mean of its divisors is an integer number (738542140).

Almost surely, 2^21252415425 is an apocalyptic number.

21252415425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21252415425 is a deficient number, since it is larger than the sum of its proper divisors (14197607295).

21252415425 is a wasteful number, since it uses less digits than its factorization.

21252415425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3602 (or 3597 counting only the distinct ones).

The product of its digits is 32000, while the sum is 33.

The spelling of 21252415425 in words is "twenty-one billion, two hundred fifty-two million, four hundred fifteen thousand, four hundred twenty-five".