20131131223 has 4 divisors (see below), whose sum is σ = 23007007120. Its totient is φ = 17255255328.

The previous prime is 20131131203. The next prime is 20131131239. The reversal of 20131131223 is 32213113102.

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 20131131223 - 2⁹ = 20131130711 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 20131131223.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20131131203) 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, 1437937938 + ... + 1437937951.

It is an arithmetic number, because the mean of its divisors is an integer number (5751751780).

Almost surely, 2^20131131223 is an apocalyptic number.

20131131223 is a deficient number, since it is larger than the sum of its proper divisors (2875875897).

20131131223 is an equidigital number, since it uses as much as digits as its factorization.

20131131223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2875875896.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 20131131223 its reverse (32213113102), we get a palindrome (52344244325).

The spelling of 20131131223 in words is "twenty billion, one hundred thirty-one million, one hundred thirty-one thousand, two hundred twenty-three".