13997913218 has 4 divisors (see below), whose sum is σ = 20996869830. Its totient is φ = 6998956608.

The previous prime is 13997913217. The next prime is 13997913221. The reversal of 13997913218 is 81231979931.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81231979931 = 233 ⋅348635107.

It can be written as a sum of positive squares in only one way, i.e., 13076608609 + 921304609 = 114353^2 + 30353^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 13997913218.

It is not an unprimeable number, because it can be changed into a prime (13997913211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3499478303 + ... + 3499478306.

Almost surely, 2^13997913218 is an apocalyptic number.

13997913218 is a deficient number, since it is larger than the sum of its proper divisors (6998956612).

13997913218 is an equidigital number, since it uses as much as digits as its factorization.

13997913218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6998956611.

The product of its digits is 734832, while the sum is 53.

The spelling of 13997913218 in words is "thirteen billion, nine hundred ninety-seven million, nine hundred thirteen thousand, two hundred eighteen".