13991859 has 20 divisors (see below), whose sum is σ = 23888304. Its totient is φ = 7995024.

The previous prime is 13991839. The next prime is 13991869. The reversal of 13991859 is 95819931.

It is not a de Polignac number, because 13991859 - 2⁵ = 13991827 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (13991839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 11772 + ... + 12905.

Almost surely, 2^13991859 is an apocalyptic number.

13991859 is a deficient number, since it is larger than the sum of its proper divisors (9896445).

13991859 is an equidigital number, since it uses as much as digits as its factorization.

13991859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24696 (or 24687 counting only the distinct ones).

The product of its digits is 87480, while the sum is 45.

The square root of 13991859 is about 3740.5693416912. The cubic root of 13991859 is about 240.9675007685.

The spelling of 13991859 in words is "thirteen million, nine hundred ninety-one thousand, eight hundred fifty-nine".