81422272 has 14 divisors (see below), whose sum is σ = 161572448. Its totient is φ = 40711104.

The previous prime is 81422207. The next prime is 81422291. The reversal of 81422272 is 27222418.

It is a self number, because there is not a number n which added to its sum of digits gives 81422272.

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 as a sum of consecutive naturals, namely, 636048 + ... + 636175.

Almost surely, 2^81422272 is an apocalyptic number.

It is an amenable number.

81422272 is a deficient number, since it is larger than the sum of its proper divisors (80150176).

81422272 is a wasteful number, since it uses less digits than its factorization.

81422272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1272235 (or 1272225 counting only the distinct ones).

The product of its digits is 3584, while the sum is 28.

The square root of 81422272 is about 9023.4290599528. The cubic root of 81422272 is about 433.4254468218.

The spelling of 81422272 in words is "eighty-one million, four hundred twenty-two thousand, two hundred seventy-two".