20977831377798 has 16 divisors (see below), whose sum is σ = 41955876996096. Its totient is φ = 6992574752520.

The previous prime is 20977831377779. The next prime is 20977831377803. The reversal of 20977831377798 is 89777313877902.

It is a congruent 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, 7639486 + ... + 10015857.

It is an arithmetic number, because the mean of its divisors is an integer number (2622242312256).

Almost surely, 2^{20977831377798} is an apocalyptic number.

20977831377798 is an abundant number, since it is smaller than the sum of its proper divisors (20978045618298).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20977831377798 is a wasteful number, since it uses less digits than its factorization.

20977831377798 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17853379.

The product of its (nonzero) digits is 1568294784, while the sum is 78.

The spelling of 20977831377798 in words is "twenty trillion, nine hundred seventy-seven billion, eight hundred thirty-one million, three hundred seventy-seven thousand, seven hundred ninety-eight".