81333332 has 24 divisors (see below), whose sum is σ = 145070016. Its totient is φ = 39892608.

The previous prime is 81333311. The next prime is 81333337. The reversal of 81333332 is 23333318.

It is a super-2 number, since 2×81333332² = 13230221788444448, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81333337) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45683 + ... + 47429.

It is an arithmetic number, because the mean of its divisors is an integer number (6044584).

Almost surely, 2^81333332 is an apocalyptic number.

It is an amenable number.

81333332 is a deficient number, since it is larger than the sum of its proper divisors (63736684).

81333332 is a wasteful number, since it uses less digits than its factorization.

81333332 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1967 (or 1965 counting only the distinct ones).

The product of its digits is 3888, while the sum is 26.

The square root of 81333332 is about 9018.4994317237. The cubic root of 81333332 is about 433.2675747685.

The spelling of 81333332 in words is "eighty-one million, three hundred thirty-three thousand, three hundred thirty-two".