7999681 has 2 divisors, whose sum is σ = 7999682. Its totient is φ = 7999680.

The previous prime is 7999669. The next prime is 7999709. The reversal of 7999681 is 1869997.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6656400 + 1343281 = 2580^2 + 1159^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7999681 is a prime.

It is a super-2 number, since 2×7999681² = 127989792203522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (7999081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3999840 + 3999841.

It is an arithmetic number, because the mean of its divisors is an integer number (3999841).

Almost surely, 2^7999681 is an apocalyptic number.

It is an amenable number.

7999681 is a deficient number, since it is larger than the sum of its proper divisors (1).

7999681 is an equidigital number, since it uses as much as digits as its factorization.

7999681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 244944, while the sum is 49.

The square root of 7999681 is about 2828.3707324182. The cubic root of 7999681 is about 199.9973416313.

The spelling of 7999681 in words is "seven million, nine hundred ninety-nine thousand, six hundred eighty-one".