21147244256 has 36 divisors (see below), whose sum is σ = 42050581776. Its totient is φ = 10468771200.

The previous prime is 21147244247. The next prime is 21147244403. The reversal of 21147244256 is 65244274112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 294041 + ... + 358823.

It is an arithmetic number, because the mean of its divisors is an integer number (1168071716).

Almost surely, 2^21147244256 is an apocalyptic number.

It is an amenable number.

21147244256 is a deficient number, since it is larger than the sum of its proper divisors (20903337520).

21147244256 is an equidigital number, since it uses as much as digits as its factorization.

21147244256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64995 (or 64886 counting only the distinct ones).

The product of its digits is 107520, while the sum is 38.

The spelling of 21147244256 in words is "twenty-one billion, one hundred forty-seven million, two hundred forty-four thousand, two hundred fifty-six".