81892124225 has 12 divisors (see below), whose sum is σ = 101722241964. Its totient is φ = 65400145920.

The previous prime is 81892124213. The next prime is 81892124231. The reversal of 81892124225 is 52242129818.

It is a Cunningham number, because it is equal to 286168²+1.

It can be written as a sum of positive squares in 6 ways, for example, as 1 + 81892124224 = 1^2 + 286168^2 .

It is not a de Polignac number, because 81892124225 - 2¹⁸ = 81891862081 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2824124 + ... + 2852973.

It is an arithmetic number, because the mean of its divisors is an integer number (8476853497).

Almost surely, 2^81892124225 is an apocalyptic number.

It is an amenable number.

81892124225 is a deficient number, since it is larger than the sum of its proper divisors (19830117739).

81892124225 is a wasteful number, since it uses less digits than its factorization.

81892124225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5677684 (or 5677679 counting only the distinct ones).

The product of its digits is 184320, while the sum is 44.

The spelling of 81892124225 in words is "eighty-one billion, eight hundred ninety-two million, one hundred twenty-four thousand, two hundred twenty-five".