81346913 has 2 divisors, whose sum is σ = 81346914. Its totient is φ = 81346912.

The previous prime is 81346879. The next prime is 81346919. The reversal of 81346913 is 31964318.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 80586529 + 760384 = 8977^2 + 872^2 .

It is a cyclic number.

It is not a de Polignac number, because 81346913 - 2¹⁰ = 81345889 is a prime.

It is equal to p_4743548 and since 81346913 and 4743548 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (81346919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40673456 + 40673457.

It is an arithmetic number, because the mean of its divisors is an integer number (40673457).

Almost surely, 2^81346913 is an apocalyptic number.

It is an amenable number.

81346913 is a deficient number, since it is larger than the sum of its proper divisors (1).

81346913 is an equidigital number, since it uses as much as digits as its factorization.

81346913 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 35.

The square root of 81346913 is about 9019.2523526066. The cubic root of 81346913 is about 433.2916890289.

The spelling of 81346913 in words is "eighty-one million, three hundred forty-six thousand, nine hundred thirteen".