81339713 has 16 divisors (see below), whose sum is σ = 106001280. Its totient is φ = 60569856.

The previous prime is 81339677. The next prime is 81339719. The reversal of 81339713 is 31793318.

It is a cyclic number.

It is not a de Polignac number, because 81339713 - 2⁶ = 81339649 is a prime.

It is a super-2 number, since 2×81339713² = 13232297821844738, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81339719) 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 in 15 ways as a sum of consecutive naturals, for example, 24743 + ... + 27836.

It is an arithmetic number, because the mean of its divisors is an integer number (6625080).

Almost surely, 2^81339713 is an apocalyptic number.

It is an amenable number.

81339713 is a deficient number, since it is larger than the sum of its proper divisors (24661567).

81339713 is a wasteful number, since it uses less digits than its factorization.

81339713 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52616.

The product of its digits is 13608, while the sum is 35.

The square root of 81339713 is about 9018.8531976078. The cubic root of 81339713 is about 433.2789051297.

The spelling of 81339713 in words is "eighty-one million, three hundred thirty-nine thousand, seven hundred thirteen".