20007131 has 4 divisors (see below), whose sum is σ = 20017272. Its totient is φ = 19996992.

The previous prime is 20007107. The next prime is 20007149. The reversal of 20007131 is 13170002.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20007131 is a prime.

It is a super-2 number, since 2×20007131² = 800570581702322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20003131) 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, 1046 + ... + 6411.

It is an arithmetic number, because the mean of its divisors is an integer number (5004318).

Almost surely, 2^20007131 is an apocalyptic number.

20007131 is a deficient number, since it is larger than the sum of its proper divisors (10141).

20007131 is an equidigital number, since it uses as much as digits as its factorization.

20007131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10140.

The product of its (nonzero) digits is 42, while the sum is 14.

The square root of 20007131 is about 4472.9331539830. The cubic root of 20007131 is about 271.4740186794.

Adding to 20007131 its reverse (13170002), we get a palindrome (33177133).

The spelling of 20007131 in words is "twenty million, seven thousand, one hundred thirty-one".