31221120331 has 8 divisors (see below), whose sum is σ = 32154265440. Its totient is φ = 30292676928.

The previous prime is 31221120317. The next prime is 31221120367. The reversal of 31221120331 is 13302112213.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 31221120331 - 2²³ = 31212731723 is a prime.

It is a super-2 number, since 2×31221120331² (a number of 22 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 = 31221120299 and 31221120308.

It is not an unprimeable number, because it can be changed into a prime (31221120031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1161946 + ... + 1188511.

It is an arithmetic number, because the mean of its divisors is an integer number (4019283180).

Almost surely, 2^31221120331 is an apocalyptic number.

31221120331 is a deficient number, since it is larger than the sum of its proper divisors (933145109).

31221120331 is a wasteful number, since it uses less digits than its factorization.

31221120331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2350853.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 31221120331 its reverse (13302112213), we get a palindrome (44523232544).

The spelling of 31221120331 in words is "thirty-one billion, two hundred twenty-one million, one hundred twenty thousand, three hundred thirty-one".