81288222 has 8 divisors (see below), whose sum is σ = 162576456. Its totient is φ = 27096072.

The previous prime is 81288217. The next prime is 81288227. The reversal of 81288222 is 22288218.

It is an interprime number because it is at equal distance from previous prime (81288217) and next prime (81288227).

It is a sphenic number, since it is the product of 3 distinct primes.

81288222 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81288227) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 6774013 + ... + 6774024.

It is an arithmetic number, because the mean of its divisors is an integer number (20322057).

Almost surely, 2^81288222 is an apocalyptic number.

81288222 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

81288222 is a wasteful number, since it uses less digits than its factorization.

81288222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13548042.

The product of its digits is 8192, while the sum is 33.

The square root of 81288222 is about 9015.9981144630. The cubic root of 81288222 is about 433.1874587230.

The spelling of 81288222 in words is "eighty-one million, two hundred eighty-eight thousand, two hundred twenty-two".