21243536744 has 64 divisors (see below), whose sum is σ = 41083621200. Its totient is φ = 10293663744.

The previous prime is 21243536729. The next prime is 21243536773. The reversal of 21243536744 is 44763534212.

It can be written as a sum of positive squares in 8 ways, for example, as 15860379844 + 5383156900 = 125938^2 + 73370^2 .

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 15 ways as a sum of consecutive naturals, for example, 13301354 + ... + 13302950.

Almost surely, 2^21243536744 is an apocalyptic number.

It is an amenable number.

21243536744 is a deficient number, since it is larger than the sum of its proper divisors (19840084456).

21243536744 is a wasteful number, since it uses less digits than its factorization.

21243536744 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2022 (or 2018 counting only the distinct ones).

The product of its digits is 483840, while the sum is 41.

The spelling of 21243536744 in words is "twenty-one billion, two hundred forty-three million, five hundred thirty-six thousand, seven hundred forty-four".