7561681 has 2 divisors, whose sum is σ = 7561682. Its totient is φ = 7561680.

The previous prime is 7561633. The next prime is 7561691. The reversal of 7561681 is 1861657.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7049025 + 512656 = 2655^2 + 716^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7561681 is a prime.

It is a super-2 number, since 2×7561681² = 114358039091522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (7561691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3780840 + 3780841.

It is an arithmetic number, because the mean of its divisors is an integer number (3780841).

Almost surely, 2^7561681 is an apocalyptic number.

It is an amenable number.

7561681 is a deficient number, since it is larger than the sum of its proper divisors (1).

7561681 is an equidigital number, since it uses as much as digits as its factorization.

7561681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10080, while the sum is 34.

The square root of 7561681 is about 2749.8510868773. The cubic root of 7561681 is about 196.2785242594.

The spelling of 7561681 in words is "seven million, five hundred sixty-one thousand, six hundred eighty-one".