81822186 has 24 divisors (see below), whose sum is σ = 177621444. Its totient is φ = 27221760.

The previous prime is 81822149. The next prime is 81822187. The reversal of 81822186 is 68122818.

It can be written as a sum of positive squares in 2 ways, for example, as 74287161 + 7535025 = 8619^2 + 2745^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 81822186.

It is not an unprimeable number, because it can be changed into a prime (81822187) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5946 + ... + 14106.

Almost surely, 2^81822186 is an apocalyptic number.

81822186 is an abundant number, since it is smaller than the sum of its proper divisors (95799258).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81822186 is a wasteful number, since it uses less digits than its factorization.

81822186 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8726 (or 8723 counting only the distinct ones).

The product of its digits is 12288, while the sum is 36.

The square root of 81822186 is about 9045.5616741029. The cubic root of 81822186 is about 434.1338930115.

The spelling of 81822186 in words is "eighty-one million, eight hundred twenty-two thousand, one hundred eighty-six".