81333333 has 12 divisors (see below), whose sum is σ = 117918528. Its totient is φ = 54020520.

The previous prime is 81333311. The next prime is 81333337. The reversal of 81333333 is 33333318.

It is not a de Polignac number, because 81333333 - 2⁹ = 81332821 is a prime.

It is a super-2 number, since 2×81333333² = 13230222113777778, which contains 22 as substring.

81333333 is a modest number, since divided by 33333 gives 813 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 81333297 and 81333306.

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 polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14235 + ... + 19112.

It is an arithmetic number, because the mean of its divisors is an integer number (9826544).

Almost surely, 2^81333333 is an apocalyptic number.

It is an amenable number.

81333333 is a deficient number, since it is larger than the sum of its proper divisors (36585195).

81333333 is a wasteful number, since it uses less digits than its factorization.

81333333 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33624 (or 33621 counting only the distinct ones).

The product of its digits is 5832, while the sum is 27.

The square root of 81333333 is about 9018.4994871653. The cubic root of 81333333 is about 433.2675765442.

The spelling of 81333333 in words is "eighty-one million, three hundred thirty-three thousand, three hundred thirty-three".