81444222 has 24 divisors (see below), whose sum is σ = 185750760. Its totient is φ = 25719120.

The previous prime is 81444217. The next prime is 81444239. The reversal of 81444222 is 22244418.

It is a super-2 number, since 2×81444222² = 13266322594370568, 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 11 ways as a sum of consecutive naturals, for example, 118729 + ... + 119412.

It is an arithmetic number, because the mean of its divisors is an integer number (7739615).

Almost surely, 2^81444222 is an apocalyptic number.

81444222 is an abundant number, since it is smaller than the sum of its proper divisors (104306538).

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

81444222 is a wasteful number, since it uses less digits than its factorization.

81444222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 238168 (or 238165 counting only the distinct ones).

The product of its digits is 4096, while the sum is 27.

The square root of 81444222 is about 9024.6452561860. The cubic root of 81444222 is about 433.4643912594.

The spelling of 81444222 in words is "eighty-one million, four hundred forty-four thousand, two hundred twenty-two".