21126440925 has 24 divisors (see below), whose sum is σ = 38810055680. Its totient is φ = 11267434800.

The previous prime is 21126440903. The next prime is 21126440963. The reversal of 21126440925 is 52904462112.

It is a happy number.

21126440925 is a `hidden beast` number, since 2 + 1 + 1 + 2 + 644 + 0 + 9 + 2 + 5 = 666.

It is not a de Polignac number, because 21126440925 - 2²⁴ = 21109663709 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21126440925.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15648541 + ... + 15649890.

Almost surely, 2^21126440925 is an apocalyptic number.

21126440925 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21126440925 is a deficient number, since it is larger than the sum of its proper divisors (17683614755).

21126440925 is a wasteful number, since it uses less digits than its factorization.

21126440925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31298450 (or 31298439 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The spelling of 21126440925 in words is "twenty-one billion, one hundred twenty-six million, four hundred forty thousand, nine hundred twenty-five".