7687681 has 4 divisors (see below), whose sum is σ = 8021952. Its totient is φ = 7353412.

The previous prime is 7687663. The next prime is 7687699. The reversal of 7687681 is 1867867.

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 an interprime number because it is at equal distance from previous prime (7687663) and next prime (7687699).

It is a cyclic number.

It is not a de Polignac number, because 7687681 - 2¹⁷ = 7556609 is a prime.

It is a super-2 number, since 2×7687681² = 118200878315522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7687651) 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, 167101 + ... + 167146.

It is an arithmetic number, because the mean of its divisors is an integer number (2005488).

Almost surely, 2^7687681 is an apocalyptic number.

It is an amenable number.

7687681 is a deficient number, since it is larger than the sum of its proper divisors (334271).

7687681 is a wasteful number, since it uses less digits than its factorization.

7687681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334270.

The product of its digits is 112896, while the sum is 43.

The square root of 7687681 is about 2772.6667668510. Note that the first 3 decimals coincide. The cubic root of 7687681 is about 197.3627182496.

The spelling of 7687681 in words is "seven million, six hundred eighty-seven thousand, six hundred eighty-one".