20423131431 has 4 divisors (see below), whose sum is σ = 27230841912. Its totient is φ = 13615420952.

The previous prime is 20423131403. The next prime is 20423131447. The reversal of 20423131431 is 13413132402.

It is a happy number.

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 20423131431 - 2⁶ = 20423131367 is a prime.

It is a super-2 number, since 2×20423131431² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20423131481) 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, 3403855236 + ... + 3403855241.

It is an arithmetic number, because the mean of its divisors is an integer number (6807710478).

Almost surely, 2^20423131431 is an apocalyptic number.

20423131431 is a deficient number, since it is larger than the sum of its proper divisors (6807710481).

20423131431 is an equidigital number, since it uses as much as digits as its factorization.

20423131431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6807710480.

The product of its (nonzero) digits is 1728, while the sum is 24.

Adding to 20423131431 its reverse (13413132402), we get a palindrome (33836263833).

The spelling of 20423131431 in words is "twenty billion, four hundred twenty-three million, one hundred thirty-one thousand, four hundred thirty-one".