81822238 has 4 divisors (see below), whose sum is σ = 122733360. Its totient is φ = 40911118.

The previous prime is 81822187. The next prime is 81822271. The reversal of 81822238 is 83222818.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20455558 + ... + 20455561.

It is an arithmetic number, because the mean of its divisors is an integer number (30683340).

Almost surely, 2^81822238 is an apocalyptic number.

81822238 is a deficient number, since it is larger than the sum of its proper divisors (40911122).

81822238 is a wasteful number, since it uses less digits than its factorization.

81822238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40911121.

The product of its digits is 12288, while the sum is 34.

The square root of 81822238 is about 9045.5645484403. The cubic root of 81822238 is about 434.1339849790.

The spelling of 81822238 in words is "eighty-one million, eight hundred twenty-two thousand, two hundred thirty-eight".