20791878399 has 48 divisors (see below), whose sum is σ = 31744627200. Its totient is φ = 13087863360.

The previous prime is 20791878361. The next prime is 20791878413. The reversal of 20791878399 is 99387819702.

It is not a de Polignac number, because 20791878399 - 2⁸ = 20791878143 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20791878319) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5394357 + ... + 5398209.

It is an arithmetic number, because the mean of its divisors is an integer number (661346400).

Almost surely, 2^20791878399 is an apocalyptic number.

20791878399 is a deficient number, since it is larger than the sum of its proper divisors (10952748801).

20791878399 is a wasteful number, since it uses less digits than its factorization.

20791878399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4212 (or 4209 counting only the distinct ones).

The product of its (nonzero) digits is 13716864, while the sum is 63.

The spelling of 20791878399 in words is "twenty billion, seven hundred ninety-one million, eight hundred seventy-eight thousand, three hundred ninety-nine".