20420333431 has 4 divisors (see below), whose sum is σ = 20422705264. Its totient is φ = 20417961600.

The previous prime is 20420333399. The next prime is 20420333443. The reversal of 20420333431 is 13433302402.

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 20420333431 - 2⁵ = 20420333399 is a prime.

It is a super-2 number, since 2×20420333431² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20420333396 and 20420333405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20420333471) 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, 1172955 + ... + 1190236.

It is an arithmetic number, because the mean of its divisors is an integer number (5105676316).

Almost surely, 2^20420333431 is an apocalyptic number.

20420333431 is a deficient number, since it is larger than the sum of its proper divisors (2371833).

20420333431 is an equidigital number, since it uses as much as digits as its factorization.

20420333431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2371832.

The product of its (nonzero) digits is 5184, while the sum is 25.

Adding to 20420333431 its reverse (13433302402), we get a palindrome (33853635833).

The spelling of 20420333431 in words is "twenty billion, four hundred twenty million, three hundred thirty-three thousand, four hundred thirty-one".