13731979391 has 4 divisors (see below), whose sum is σ = 14788285512. Its totient is φ = 12675673272.

The previous prime is 13731979369. The next prime is 13731979397. The reversal of 13731979391 is 19397913731.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 13731979391 - 2¹⁸ = 13731717247 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13731979397) 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, 528153041 + ... + 528153066.

It is an arithmetic number, because the mean of its divisors is an integer number (3697071378).

Almost surely, 2^13731979391 is an apocalyptic number.

13731979391 is a deficient number, since it is larger than the sum of its proper divisors (1056306121).

13731979391 is a wasteful number, since it uses less digits than its factorization.

13731979391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1056306120.

The product of its digits is 964467, while the sum is 53.

The spelling of 13731979391 in words is "thirteen billion, seven hundred thirty-one million, nine hundred seventy-nine thousand, three hundred ninety-one".