81229056 has 36 divisors (see below), whose sum is σ = 216189792. Its totient is φ = 27076096.

The previous prime is 81229051. The next prime is 81229069. The reversal of 81229056 is 65092218.

It is a super-2 number, since 2×81229056² = 13196319077302272, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81229051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 52116 + ... + 53651.

It is an arithmetic number, because the mean of its divisors is an integer number (6005272).

Almost surely, 2^81229056 is an apocalyptic number.

It is an amenable number.

81229056 is an abundant number, since it is smaller than the sum of its proper divisors (134960736).

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

81229056 is a wasteful number, since it uses less digits than its factorization.

81229056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105786 (or 105772 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 81229056 is about 9012.7163496917. The cubic root of 81229056 is about 433.0823340634.

The spelling of 81229056 in words is "eighty-one million, two hundred twenty-nine thousand, fifty-six".