81965699 has 2 divisors, whose sum is σ = 81965700. Its totient is φ = 81965698.

The previous prime is 81965647. The next prime is 81965743. The reversal of 81965699 is 99656918.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81965699 - 2¹⁶ = 81900163 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81965699.

It is not a weakly prime, because it can be changed into another prime (81965099) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40982849 + 40982850.

It is an arithmetic number, because the mean of its divisors is an integer number (40982850).

Almost surely, 2^81965699 is an apocalyptic number.

81965699 is a deficient number, since it is larger than the sum of its proper divisors (1).

81965699 is an equidigital number, since it uses as much as digits as its factorization.

81965699 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1049760, while the sum is 53.

The square root of 81965699 is about 9053.4909841453. The cubic root of 81965699 is about 434.3875628684.

The spelling of 81965699 in words is "eighty-one million, nine hundred sixty-five thousand, six hundred ninety-nine".