81112492031 has 4 divisors (see below), whose sum is σ = 83729024064. Its totient is φ = 78495960000.

The previous prime is 81112491959. The next prime is 81112492033. The reversal of 81112492031 is 13029421118.

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-81112492031 is a prime.

It is a super-2 number, since 2×81112492031² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81112492033) 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, 1308265970 + ... + 1308266031.

It is an arithmetic number, because the mean of its divisors is an integer number (20932256016).

Almost surely, 2^81112492031 is an apocalyptic number.

81112492031 is a deficient number, since it is larger than the sum of its proper divisors (2616532033).

81112492031 is a wasteful number, since it uses less digits than its factorization.

81112492031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2616532032.

The product of its (nonzero) digits is 3456, while the sum is 32.

The spelling of 81112492031 in words is "eighty-one billion, one hundred twelve million, four hundred ninety-two thousand, thirty-one".