31431112123 has 4 divisors (see below), whose sum is σ = 31569575400. Its totient is φ = 31292648848.

The previous prime is 31431112109. The next prime is 31431112147. The reversal of 31431112123 is 32121113413.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31431112123 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31431112094 and 31431112103.

It is not an unprimeable number, because it can be changed into a prime (31431112183) 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, 69231298 + ... + 69231751.

It is an arithmetic number, because the mean of its divisors is an integer number (7892393850).

Almost surely, 2^31431112123 is an apocalyptic number.

31431112123 is a deficient number, since it is larger than the sum of its proper divisors (138463277).

31431112123 is a wasteful number, since it uses less digits than its factorization.

31431112123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138463276.

The product of its digits is 432, while the sum is 22.

Adding to 31431112123 its reverse (32121113413), we get a palindrome (63552225536).

The spelling of 31431112123 in words is "thirty-one billion, four hundred thirty-one million, one hundred twelve thousand, one hundred twenty-three".