31000220431 has 16 divisors (see below), whose sum is σ = 32836579200. Its totient is φ = 29184569568.

The previous prime is 31000220401. The next prime is 31000220527. The reversal of 31000220431 is 13402200013.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 31000220431 - 2⁵ = 31000220399 is a prime.

It is a super-2 number, since 2×31000220431² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31000220401) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7932580 + ... + 7936486.

It is an arithmetic number, because the mean of its divisors is an integer number (2052286200).

Almost surely, 2^31000220431 is an apocalyptic number.

31000220431 is a deficient number, since it is larger than the sum of its proper divisors (1836358769).

31000220431 is a wasteful number, since it uses less digits than its factorization.

31000220431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6438.

The product of its (nonzero) digits is 144, while the sum is 16.

Adding to 31000220431 its reverse (13402200013), we get a palindrome (44402420444).

The spelling of 31000220431 in words is "thirty-one billion, two hundred twenty thousand, four hundred thirty-one".