31553212231 has 4 divisors (see below), whose sum is σ = 32148555912. Its totient is φ = 30957868552.

The previous prime is 31553212217. The next prime is 31553212241. The reversal of 31553212231 is 13221235513.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13221235513 = 557 ⋅23736509.

It is a cyclic number.

It is not a de Polignac number, because 31553212231 - 2⁹ = 31553211719 is a prime.

It is a super-2 number, since 2×31553212231² (a number of 22 digits) contains 22 as substring.

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 31553212231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31553212211) 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, 297671761 + ... + 297671866.

It is an arithmetic number, because the mean of its divisors is an integer number (8037138978).

Almost surely, 2^31553212231 is an apocalyptic number.

31553212231 is a deficient number, since it is larger than the sum of its proper divisors (595343681).

31553212231 is an equidigital number, since it uses as much as digits as its factorization.

31553212231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 595343680.

The product of its digits is 5400, while the sum is 28.

Adding to 31553212231 its reverse (13221235513), we get a palindrome (44774447744).

The spelling of 31553212231 in words is "thirty-one billion, five hundred fifty-three million, two hundred twelve thousand, two hundred thirty-one".