21124064425 has 24 divisors (see below), whose sum is σ = 27800767512. Its totient is φ = 15867264000.

The previous prime is 21124064393. The next prime is 21124064431. The reversal of 21124064425 is 52446042112.

It can be written as a sum of positive squares in 12 ways, for example, as 14867412624 + 6256651801 = 121932^2 + 79099^2 .

It is not a de Polignac number, because 21124064425 - 2⁵ = 21124064393 is a prime.

It is a Duffinian 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, 119895 + ... + 237955.

It is an arithmetic number, because the mean of its divisors is an integer number (1158365313).

Almost surely, 2^21124064425 is an apocalyptic number.

21124064425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21124064425 is a deficient number, since it is larger than the sum of its proper divisors (6676703087).

21124064425 is a wasteful number, since it uses less digits than its factorization.

21124064425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118509 (or 118504 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 31.

The spelling of 21124064425 in words is "twenty-one billion, one hundred twenty-four million, sixty-four thousand, four hundred twenty-five".