81822190 has 16 divisors (see below), whose sum is σ = 155943792. Its totient is φ = 30803584.

The previous prime is 81822187. The next prime is 81822271. The reversal of 81822190 is 9122818.

It is a happy number.

It is a super-2 number, since 2×81822190² = 13389741552792200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 240484 + ... + 240823.

It is an arithmetic number, because the mean of its divisors is an integer number (9746487).

Almost surely, 2^81822190 is an apocalyptic number.

81822190 is a deficient number, since it is larger than the sum of its proper divisors (74121602).

81822190 is a wasteful number, since it uses less digits than its factorization.

81822190 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 481331.

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 81822190 is about 9045.5618952058. The cubic root of 81822190 is about 434.1339000859.

The spelling of 81822190 in words is "eighty-one million, eight hundred twenty-two thousand, one hundred ninety".