21254477525 has 48 divisors (see below), whose sum is σ = 27374956224. Its totient is φ = 16359598080.

The previous prime is 21254477467. The next prime is 21254477549. The reversal of 21254477525 is 52577445212.

It is not a de Polignac number, because 21254477525 - 2²⁰ = 21253428949 is a prime.

It is a Duffinian number.

It is a congruent number.

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, 33054854 + ... + 33055496.

It is an arithmetic number, because the mean of its divisors is an integer number (570311588).

Almost surely, 2^21254477525 is an apocalyptic number.

21254477525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21254477525 is a deficient number, since it is larger than the sum of its proper divisors (6120478699).

21254477525 is a wasteful number, since it uses less digits than its factorization.

21254477525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1110 (or 1105 counting only the distinct ones).

The product of its digits is 784000, while the sum is 44.

The spelling of 21254477525 in words is "twenty-one billion, two hundred fifty-four million, four hundred seventy-seven thousand, five hundred twenty-five".