20018479 has 4 divisors (see below), whose sum is σ = 21558376. Its totient is φ = 18478584.

The previous prime is 20018477. The next prime is 20018489. The reversal of 20018479 is 97481002.

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 20018479 - 2¹ = 20018477 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20018479.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20018477) 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, 769929 + ... + 769954.

It is an arithmetic number, because the mean of its divisors is an integer number (5389594).

Almost surely, 2^20018479 is an apocalyptic number.

20018479 is a deficient number, since it is larger than the sum of its proper divisors (1539897).

20018479 is a wasteful number, since it uses less digits than its factorization.

20018479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1539896.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 20018479 is about 4474.2014930041. The cubic root of 20018479 is about 271.5253354640.

The spelling of 20018479 in words is "twenty million, eighteen thousand, four hundred seventy-nine".