81179933 has 2 divisors, whose sum is σ = 81179934. Its totient is φ = 81179932.

The previous prime is 81179927. The next prime is 81179939. The reversal of 81179933 is 33997118.

It is a balanced prime because it is at equal distance from previous prime (81179927) and next prime (81179939).

It can be written as a sum of positive squares in only one way, i.e., 46758244 + 34421689 = 6838^2 + 5867^2 .

It is a cyclic number.

It is not a de Polignac number, because 81179933 - 2¹² = 81175837 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81179939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40589966 + 40589967.

It is an arithmetic number, because the mean of its divisors is an integer number (40589967).

Almost surely, 2^81179933 is an apocalyptic number.

It is an amenable number.

81179933 is a deficient number, since it is larger than the sum of its proper divisors (1).

81179933 is an equidigital number, since it uses as much as digits as its factorization.

81179933 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40824, while the sum is 41.

The square root of 81179933 is about 9009.9907325147. The cubic root of 81179933 is about 432.9950147613.

The spelling of 81179933 in words is "eighty-one million, one hundred seventy-nine thousand, nine hundred thirty-three".