31220121312231 has 8 divisors (see below), whose sum is σ = 41699730044544. Its totient is φ = 20776963394040.

The previous prime is 31220121312181. The next prime is 31220121312253. The reversal of 31220121312231 is 13221312102213.

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

It is not a de Polignac number, because 31220121312231 - 2¹⁷ = 31220121181159 is a prime.

It is a super-2 number, since 2×31220121312231² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31220121311231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9112701531 + ... + 9112704956.

It is an arithmetic number, because the mean of its divisors is an integer number (5212466255568).

Almost surely, 2^{31220121312231} is an apocalyptic number.

31220121312231 is a deficient number, since it is larger than the sum of its proper divisors (10479608732313).

31220121312231 is a wasteful number, since it uses less digits than its factorization.

31220121312231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18225407061.

The product of its (nonzero) digits is 864, while the sum is 24.

Adding to 31220121312231 its reverse (13221312102213), we get a palindrome (44441433414444).

The spelling of 31220121312231 in words is "thirty-one trillion, two hundred twenty billion, one hundred twenty-one million, three hundred twelve thousand, two hundred thirty-one".