7993681 has 2 divisors, whose sum is σ = 7993682. Its totient is φ = 7993680.

The previous prime is 7993679. The next prime is 7993693. The reversal of 7993681 is 1863997.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5803281 + 2190400 = 2409^2 + 1480^2 .

It is an emirp because it is prime and its reverse (1863997) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7993681 - 2¹ = 7993679 is a prime.

It is a super-2 number, since 2×7993681² = 127797871859522, which contains 22 as substring.

Together with 7993679, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (7993651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3996840 + 3996841.

It is an arithmetic number, because the mean of its divisors is an integer number (3996841).

Almost surely, 2^7993681 is an apocalyptic number.

It is an amenable number.

7993681 is a deficient number, since it is larger than the sum of its proper divisors (1).

7993681 is an equidigital number, since it uses as much as digits as its factorization.

7993681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 81648, while the sum is 43.

The square root of 7993681 is about 2827.3098521386. The cubic root of 7993681 is about 199.9473277961.

The spelling of 7993681 in words is "seven million, nine hundred ninety-three thousand, six hundred eighty-one".