31032220231 has 4 divisors (see below), whose sum is σ = 32665495000. Its totient is φ = 29398945464.

The previous prime is 31032220229. The next prime is 31032220249. The reversal of 31032220231 is 13202223013.

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 31032220231 - 2¹ = 31032220229 is a prime.

It is a super-2 number, since 2×31032220231² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 1633274749 = 31032220231 / (3 + 1 + 0 + 3 + 2 + 2 + 2 + 0 + 2 + 3 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31032220199 and 31032220208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31032220201) 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, 816637356 + ... + 816637393.

It is an arithmetic number, because the mean of its divisors is an integer number (8166373750).

Almost surely, 2^31032220231 is an apocalyptic number.

31032220231 is a deficient number, since it is larger than the sum of its proper divisors (1633274769).

31032220231 is a wasteful number, since it uses less digits than its factorization.

31032220231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1633274768.

The product of its (nonzero) digits is 432, while the sum is 19.

Adding to 31032220231 its reverse (13202223013), we get a palindrome (44234443244).

The spelling of 31032220231 in words is "thirty-one billion, thirty-two million, two hundred twenty thousand, two hundred thirty-one".