20939417791 has 8 divisors (see below), whose sum is σ = 21165587168. Its totient is φ = 20714400000.

The previous prime is 20939417789. The next prime is 20939417809. The reversal of 20939417791 is 19771493902.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20939417791 - 2¹ = 20939417789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20939417711) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 251310 + ... + 324091.

It is an arithmetic number, because the mean of its divisors is an integer number (2645698396).

Almost surely, 2^20939417791 is an apocalyptic number.

20939417791 is a deficient number, since it is larger than the sum of its proper divisors (226169377).

20939417791 is a wasteful number, since it uses less digits than its factorization.

20939417791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 575793.

The product of its (nonzero) digits is 857304, while the sum is 52.

The spelling of 20939417791 in words is "twenty billion, nine hundred thirty-nine million, four hundred seventeen thousand, seven hundred ninety-one".