21753366724 has 6 divisors (see below), whose sum is σ = 38068391774. Its totient is φ = 10876683360.

The previous prime is 21753366689. The next prime is 21753366731. The reversal of 21753366724 is 42766335712.

It can be written as a sum of positive squares in only one way, i.e., 12194784900 + 9558581824 = 110430^2 + 97768^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2719170837 + ... + 2719170844.

Almost surely, 2^21753366724 is an apocalyptic number.

It is an amenable number.

21753366724 is a deficient number, since it is larger than the sum of its proper divisors (16315025050).

21753366724 is a wasteful number, since it uses less digits than its factorization.

21753366724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5438341685 (or 5438341683 counting only the distinct ones).

The product of its digits is 1270080, while the sum is 46.

The spelling of 21753366724 in words is "twenty-one billion, seven hundred fifty-three million, three hundred sixty-six thousand, seven hundred twenty-four".