21374683556 has 12 divisors (see below), whose sum is σ = 37678731468. Its totient is φ = 10609331712.

The previous prime is 21374683549. The next prime is 21374683571. The reversal of 21374683556 is 65538647312.

It can be written as a sum of positive squares in 2 ways, for example, as 5653536100 + 15721147456 = 75190^2 + 125384^2 .

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 3 ways as a sum of consecutive naturals, for example, 19501901 + ... + 19502996.

It is an arithmetic number, because the mean of its divisors is an integer number (3139894289).

Almost surely, 2^21374683556 is an apocalyptic number.

It is an amenable number.

21374683556 is a deficient number, since it is larger than the sum of its proper divisors (16304047912).

21374683556 is a wasteful number, since it uses less digits than its factorization.

21374683556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39005038 (or 39005036 counting only the distinct ones).

The product of its digits is 3628800, while the sum is 50.

The spelling of 21374683556 in words is "twenty-one billion, three hundred seventy-four million, six hundred eighty-three thousand, five hundred fifty-six".