21424772525 has 12 divisors (see below), whose sum is σ = 28610312052. Its totient is φ = 15821370240.

The previous prime is 21424772513. The next prime is 21424772531. The reversal of 21424772525 is 52527742412.

It can be written as a sum of positive squares in 6 ways, for example, as 1028933929 + 20395838596 = 32077^2 + 142814^2 .

It is not a de Polignac number, because 21424772525 - 2²⁴ = 21407995309 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 32960864 + ... + 32961513.

It is an arithmetic number, because the mean of its divisors is an integer number (2384192671).

Almost surely, 2^21424772525 is an apocalyptic number.

21424772525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21424772525 is a deficient number, since it is larger than the sum of its proper divisors (7185539527).

21424772525 is a wasteful number, since it uses less digits than its factorization.

21424772525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65922400 (or 65922395 counting only the distinct ones).

The product of its digits is 313600, while the sum is 41.

The spelling of 21424772525 in words is "twenty-one billion, four hundred twenty-four million, seven hundred seventy-two thousand, five hundred twenty-five".