71680681 has 4 divisors (see below), whose sum is σ = 71730000. Its totient is φ = 71631364.

The previous prime is 71680667. The next prime is 71680733. The reversal of 71680681 is 18608617.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71680681 is a prime.

It is a super-2 number, since 2×71680681² = 10276240057247522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 71680681.

It is not an unprimeable number, because it can be changed into a prime (71680621) 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 3 ways as a sum of consecutive naturals, for example, 22411 + ... + 25408.

It is an arithmetic number, because the mean of its divisors is an integer number (17932500).

Almost surely, 2^71680681 is an apocalyptic number.

It is an amenable number.

71680681 is a deficient number, since it is larger than the sum of its proper divisors (49319).

71680681 is a wasteful number, since it uses less digits than its factorization.

71680681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49318.

The product of its (nonzero) digits is 16128, while the sum is 37.

The square root of 71680681 is about 8466.4444130934. Note that the first 4 decimals coincide. The cubic root of 71680681 is about 415.4008436530.

It can be divided in two parts, 71680 and 681, that added together give a square (72361 = 269²).

The spelling of 71680681 in words is "seventy-one million, six hundred eighty thousand, six hundred eighty-one".