31031221123 has 24 divisors (see below), whose sum is σ = 37872945024. Its totient is φ = 25318137600.

The previous prime is 31031221057. The next prime is 31031221127. The reversal of 31031221123 is 32112213013.

It is not a de Polignac number, because 31031221123 - 2³³ = 22441286531 is a prime.

It is a super-2 number, since 2×31031221123² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 31031221123.

It is not an unprimeable number, because it can be changed into a prime (31031221127) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 74790 + ... + 260107.

It is an arithmetic number, because the mean of its divisors is an integer number (1578039376).

Almost surely, 2^31031221123 is an apocalyptic number.

31031221123 is a deficient number, since it is larger than the sum of its proper divisors (6841723901).

31031221123 is a wasteful number, since it uses less digits than its factorization.

31031221123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 335003 (or 334996 counting only the distinct ones).

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

Adding to 31031221123 its reverse (32112213013), we get a palindrome (63143434136).

The spelling of 31031221123 in words is "thirty-one billion, thirty-one million, two hundred twenty-one thousand, one hundred twenty-three".