31021142123 has 4 divisors (see below), whose sum is σ = 31042851840. Its totient is φ = 30999432408.

The previous prime is 31021142101. The next prime is 31021142137. The reversal of 31021142123 is 32124112013.

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

It is a cyclic number.

It is not a de Polignac number, because 31021142123 - 2¹⁸ = 31020879979 is a prime.

It is a super-2 number, since 2×31021142123² (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 = 31021142095 and 31021142104.

It is not an unprimeable number, because it can be changed into a prime (31021142423) 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, 10852715 + ... + 10855572.

It is an arithmetic number, because the mean of its divisors is an integer number (7760712960).

Almost surely, 2^31021142123 is an apocalyptic number.

31021142123 is a deficient number, since it is larger than the sum of its proper divisors (21709717).

31021142123 is a wasteful number, since it uses less digits than its factorization.

31021142123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21709716.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 31021142123 its reverse (32124112013), we get a palindrome (63145254136).

The spelling of 31021142123 in words is "thirty-one billion, twenty-one million, one hundred forty-two thousand, one hundred twenty-three".