7681657 has 2 divisors, whose sum is σ = 7681658. Its totient is φ = 7681656.

The previous prime is 7681651. The next prime is 7681691. The reversal of 7681657 is 7561867.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6071296 + 1610361 = 2464^2 + 1269^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7681657 is a prime.

It is not a weakly prime, because it can be changed into another prime (7681651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3840828 + 3840829.

It is an arithmetic number, because the mean of its divisors is an integer number (3840829).

Almost surely, 2^7681657 is an apocalyptic number.

It is an amenable number.

7681657 is a deficient number, since it is larger than the sum of its proper divisors (1).

7681657 is an equidigital number, since it uses as much as digits as its factorization.

7681657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 70560, while the sum is 40.

The square root of 7681657 is about 2771.5802351727. The cubic root of 7681657 is about 197.3111542088.

It can be divided in two parts, 7681 and 657, that added together give a palindrome (8338).

The spelling of 7681657 in words is "seven million, six hundred eighty-one thousand, six hundred fifty-seven".