81164833 has 2 divisors, whose sum is σ = 81164834. Its totient is φ = 81164832.

The previous prime is 81164819. The next prime is 81164873. The reversal of 81164833 is 33846118.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 80784144 + 380689 = 8988^2 + 617^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81164833 is a prime.

It is not a weakly prime, because it can be changed into another prime (81164803) 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 as a sum of consecutive naturals, namely, 40582416 + 40582417.

It is an arithmetic number, because the mean of its divisors is an integer number (40582417).

Almost surely, 2^81164833 is an apocalyptic number.

It is an amenable number.

81164833 is a deficient number, since it is larger than the sum of its proper divisors (1).

81164833 is an equidigital number, since it uses as much as digits as its factorization.

81164833 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13824, while the sum is 34.

The square root of 81164833 is about 9009.1527348580. The cubic root of 81164833 is about 432.9681664589.

The spelling of 81164833 in words is "eighty-one million, one hundred sixty-four thousand, eight hundred thirty-three".