81056713 has 4 divisors (see below), whose sum is σ = 83033748. Its totient is φ = 79079680.

The previous prime is 81056699. The next prime is 81056741. The reversal of 81056713 is 31765018.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4108729 + 76947984 = 2027^2 + 8772^2 .

It is a cyclic number.

It is not a de Polignac number, because 81056713 - 2⁹ = 81056201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81056743) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 988456 + ... + 988537.

It is an arithmetic number, because the mean of its divisors is an integer number (20758437).

Almost surely, 2^81056713 is an apocalyptic number.

It is an amenable number.

81056713 is a deficient number, since it is larger than the sum of its proper divisors (1977035).

81056713 is a wasteful number, since it uses less digits than its factorization.

81056713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1977034.

The product of its (nonzero) digits is 5040, while the sum is 31.

The square root of 81056713 is about 9003.1501709124. The cubic root of 81056713 is about 432.7758281510.

The spelling of 81056713 in words is "eighty-one million, fifty-six thousand, seven hundred thirteen".