20978093992 has 16 divisors (see below), whose sum is σ = 39336815700. Its totient is φ = 10488276480.

The previous prime is 20978093963. The next prime is 20978093999. The reversal of 20978093992 is 29939087902.

It can be written as a sum of positive squares in 2 ways, for example, as 19652114596 + 1325979396 = 140186^2 + 36414^2 .

It is not an unprimeable number, because it can be changed into a prime (20978093999) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28984 + ... + 206872.

Almost surely, 2^20978093992 is an apocalyptic number.

It is an amenable number.

20978093992 is a deficient number, since it is larger than the sum of its proper divisors (18358721708).

20978093992 is a wasteful number, since it uses less digits than its factorization.

20978093992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 192636 (or 192632 counting only the distinct ones).

The product of its (nonzero) digits is 4408992, while the sum is 58.

The spelling of 20978093992 in words is "twenty billion, nine hundred seventy-eight million, ninety-three thousand, nine hundred ninety-two".