20009131 has 4 divisors (see below), whose sum is σ = 20040064. Its totient is φ = 19978200.

The previous prime is 20009117. The next prime is 20009137. The reversal of 20009131 is 13190002.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20009131 is a prime.

It is a super-2 number, since 2×20009131² = 800730646750322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20009137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14475 + ... + 15796.

It is an arithmetic number, because the mean of its divisors is an integer number (5010016).

Almost surely, 2^20009131 is an apocalyptic number.

20009131 is a deficient number, since it is larger than the sum of its proper divisors (30933).

20009131 is an equidigital number, since it uses as much as digits as its factorization.

20009131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30932.

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 20009131 is about 4473.1567153410. The cubic root of 20009131 is about 271.4830642867.

Adding to 20009131 its reverse (13190002), we get a palindrome (33199133).

The spelling of 20009131 in words is "twenty million, nine thousand, one hundred thirty-one".