31516211123 has 4 divisors (see below), whose sum is σ = 31657539648. Its totient is φ = 31374882600.

The previous prime is 31516211033. The next prime is 31516211171. The reversal of 31516211123 is 32111261513.

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 31516211123 - 2¹⁸ = 31515948979 is a prime.

It is a super-2 number, since 2×31516211123² (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 = 31516211092 and 31516211101.

It is not an unprimeable number, because it can be changed into a prime (31516214123) 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, 70663928 + ... + 70664373.

It is an arithmetic number, because the mean of its divisors is an integer number (7914384912).

Almost surely, 2^31516211123 is an apocalyptic number.

31516211123 is a deficient number, since it is larger than the sum of its proper divisors (141328525).

31516211123 is a wasteful number, since it uses less digits than its factorization.

31516211123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141328524.

The product of its digits is 1080, while the sum is 26.

Adding to 31516211123 its reverse (32111261513), we get a palindrome (63627472636).

The spelling of 31516211123 in words is "thirty-one billion, five hundred sixteen million, two hundred eleven thousand, one hundred twenty-three".