20973985442 has 16 divisors (see below), whose sum is σ = 31551276120. Its totient is φ = 10456915968.

The previous prime is 20973985397. The next prime is 20973985457. The reversal of 20973985442 is 24458937902.

It can be written as a sum of positive squares in 4 ways, for example, as 19007861161 + 1966124281 = 137869^2 + 44341^2 .

It is a Smith number, since the sum of its digits (53) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2824118 + ... + 2831534.

Almost surely, 2^20973985442 is an apocalyptic number.

20973985442 is a deficient number, since it is larger than the sum of its proper divisors (10577290678).

20973985442 is a wasteful number, since it uses less digits than its factorization.

20973985442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11285.

The product of its (nonzero) digits is 4354560, while the sum is 53.

The spelling of 20973985442 in words is "twenty billion, nine hundred seventy-three million, nine hundred eighty-five thousand, four hundred forty-two".