20131559 has 4 divisors (see below), whose sum is σ = 23007504. Its totient is φ = 17255616.

The previous prime is 20131549. The next prime is 20131561. The reversal of 20131559 is 95513102.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 20131559 - 2⁴ = 20131543 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20131549) 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, 1437962 + ... + 1437975.

It is an arithmetic number, because the mean of its divisors is an integer number (5751876).

Almost surely, 2^20131559 is an apocalyptic number.

20131559 is a deficient number, since it is larger than the sum of its proper divisors (2875945).

20131559 is an equidigital number, since it uses as much as digits as its factorization.

20131559 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2875944.

The product of its (nonzero) digits is 1350, while the sum is 26.

The square root of 20131559 is about 4486.8205892369. The cubic root of 20131559 is about 272.0356381721.

The spelling of 20131559 in words is "twenty million, one hundred thirty-one thousand, five hundred fifty-nine".