81122825 has 24 divisors (see below), whose sum is σ = 116599680. Its totient is φ = 54835200.

The previous prime is 81122819. The next prime is 81122869. The reversal of 81122825 is 52822118.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-81122825 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9161 + ... + 15689.

It is an arithmetic number, because the mean of its divisors is an integer number (4858320).

Almost surely, 2^81122825 is an apocalyptic number.

It is an amenable number.

81122825 is a deficient number, since it is larger than the sum of its proper divisors (35476855).

81122825 is a wasteful number, since it uses less digits than its factorization.

81122825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6617 (or 6612 counting only the distinct ones).

The product of its digits is 2560, while the sum is 29.

The square root of 81122825 is about 9006.8210263111. The cubic root of 81122825 is about 432.8934573154.

The spelling of 81122825 in words is "eighty-one million, one hundred twenty-two thousand, eight hundred twenty-five".