81757333 has 6 divisors (see below), whose sum is σ = 95105526. Its totient is φ = 70077672.

The previous prime is 81757327. The next prime is 81757363. The reversal of 81757333 is 33375718.

It can be written as a sum of positive squares in only one way, i.e., 80407089 + 1350244 = 8967^2 + 1162^2 .

It is a de Polignac number, because none of the positive numbers 2^k-81757333 is a prime.

It is a super-2 number, since 2×81757333² = 13368522998545778, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81757292 and 81757301.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81757363) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 834210 + ... + 834307.

It is an arithmetic number, because the mean of its divisors is an integer number (15850921).

Almost surely, 2^81757333 is an apocalyptic number.

It is an amenable number.

81757333 is a deficient number, since it is larger than the sum of its proper divisors (13348193).

81757333 is a wasteful number, since it uses less digits than its factorization.

81757333 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1668531 (or 1668524 counting only the distinct ones).

The product of its digits is 52920, while the sum is 37.

The square root of 81757333 is about 9041.9761667459. The cubic root of 81757333 is about 434.0191632190.

The spelling of 81757333 in words is "eighty-one million, seven hundred fifty-seven thousand, three hundred thirty-three".