13981579 has 4 divisors (see below), whose sum is σ = 14306776. Its totient is φ = 13656384.

The previous prime is 13981577. The next prime is 13981601. The reversal of 13981579 is 97518931.

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 13981579 - 2¹ = 13981577 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (43), and also a Moran number because the ratio is a prime number: 325153 = 13981579 / (1 + 3 + 9 + 8 + 1 + 5 + 7 + 9).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13981573) 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, 162534 + ... + 162619.

It is an arithmetic number, because the mean of its divisors is an integer number (3576694).

Almost surely, 2^13981579 is an apocalyptic number.

13981579 is a deficient number, since it is larger than the sum of its proper divisors (325197).

13981579 is an equidigital number, since it uses as much as digits as its factorization.

13981579 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 325196.

The product of its digits is 68040, while the sum is 43.

The square root of 13981579 is about 3739.1949668344. The cubic root of 13981579 is about 240.9084723287.

It can be divided in two parts, 139 and 81579, that added together give a palindrome (81718).

The spelling of 13981579 in words is "thirteen million, nine hundred eighty-one thousand, five hundred seventy-nine".