81292844 has 12 divisors (see below), whose sum is σ = 150630984. Its totient is φ = 38255424.

The previous prime is 81292843. The next prime is 81292859. The reversal of 81292844 is 44829218.

It is a junction number, because it is equal to n+sod(n) for n = 81292798 and 81292807.

It is not an unprimeable number, because it can be changed into a prime (81292843) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 597674 + ... + 597809.

It is an arithmetic number, because the mean of its divisors is an integer number (12552582).

Almost surely, 2^81292844 is an apocalyptic number.

It is an amenable number.

81292844 is a deficient number, since it is larger than the sum of its proper divisors (69338140).

81292844 is a wasteful number, since it uses less digits than its factorization.

81292844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1195504 (or 1195502 counting only the distinct ones).

The product of its digits is 36864, while the sum is 38.

The square root of 81292844 is about 9016.2544329672. The cubic root of 81292844 is about 433.1956688279.

The spelling of 81292844 in words is "eighty-one million, two hundred ninety-two thousand, eight hundred forty-four".