31031220423 has 16 divisors (see below), whose sum is σ = 47289007616. Its totient is φ = 17730874080.

The previous prime is 31031220401. The next prime is 31031220439. The reversal of 31031220423 is 32402213013.

It is not a de Polignac number, because 31031220423 - 2⁶ = 31031220359 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

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 31031220423.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31031220463) 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, 311253 + ... + 398673.

It is an arithmetic number, because the mean of its divisors is an integer number (2955562976).

Almost surely, 2^31031220423 is an apocalyptic number.

31031220423 is a deficient number, since it is larger than the sum of its proper divisors (16257787193).

31031220423 is a wasteful number, since it uses less digits than its factorization.

31031220423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104334.

The product of its (nonzero) digits is 864, while the sum is 21.

Adding to 31031220423 its reverse (32402213013), we get a palindrome (63433433436).

The spelling of 31031220423 in words is "thirty-one billion, thirty-one million, two hundred twenty thousand, four hundred twenty-three".