13897991779 has 16 divisors (see below), whose sum is σ = 16220986560. Its totient is φ = 11662041600.

The previous prime is 13897991749. The next prime is 13897991869. The reversal of 13897991779 is 97719979831.

It is a cyclic number.

It is not a de Polignac number, because 13897991779 - 2⁹ = 13897991267 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13897991729) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47514 + ... + 173359.

It is an arithmetic number, because the mean of its divisors is an integer number (1013811660).

Almost surely, 2^13897991779 is an apocalyptic number.

13897991779 is a deficient number, since it is larger than the sum of its proper divisors (2322994781).

13897991779 is a wasteful number, since it uses less digits than its factorization.

13897991779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221070.

The product of its digits is 54010152, while the sum is 70.

The spelling of 13897991779 in words is "thirteen billion, eight hundred ninety-seven million, nine hundred ninety-one thousand, seven hundred seventy-nine".