81800822 has 24 divisors (see below), whose sum is σ = 130258800. Its totient is φ = 38480960.

The previous prime is 81800819. The next prime is 81800843. The reversal of 81800822 is 22800818.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 97079 + ... + 97917.

It is an arithmetic number, because the mean of its divisors is an integer number (5427450).

Almost surely, 2^81800822 is an apocalyptic number.

81800822 is a gapful number since it is divisible by the number (82) formed by its first and last digit.

81800822 is a deficient number, since it is larger than the sum of its proper divisors (48457978).

81800822 is a wasteful number, since it uses less digits than its factorization.

81800822 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 952 (or 911 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 29.

The square root of 81800822 is about 9044.3806863710. The cubic root of 81800822 is about 434.0961052007.

The spelling of 81800822 in words is "eighty-one million, eight hundred thousand, eight hundred twenty-two".