20311320231023 has 4 divisors (see below), whose sum is σ = 20351224593480. Its totient is φ = 20271415868568.

The previous prime is 20311320230987. The next prime is 20311320231029. The reversal of 20311320231023 is 32013202311302.

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 20311320231023 - 2²² = 20311316036719 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 20311320231023.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20311320231029) 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, 19952180465 + ... + 19952181482.

It is an arithmetic number, because the mean of its divisors is an integer number (5087806148370).

Almost surely, 2^{20311320231023} is an apocalyptic number.

20311320231023 is a deficient number, since it is larger than the sum of its proper divisors (39904362457).

20311320231023 is an equidigital number, since it uses as much as digits as its factorization.

20311320231023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39904362456.

The product of its (nonzero) digits is 1296, while the sum is 23.

Adding to 20311320231023 its reverse (32013202311302), we get a palindrome (52324522542325).

The spelling of 20311320231023 in words is "twenty trillion, three hundred eleven billion, three hundred twenty million, two hundred thirty-one thousand, twenty-three".