7561810961 has 2 divisors, whose sum is σ = 7561810962. Its totient is φ = 7561810960.

The previous prime is 7561810943. The next prime is 7561811011. The reversal of 7561810961 is 1690181657.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4220970961 + 3340840000 = 64969^2 + 57800^2 .

It is a cyclic number.

It is not a de Polignac number, because 7561810961 - 2¹⁸ = 7561548817 is a prime.

It is not a weakly prime, because it can be changed into another prime (7561819961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3780905480 + 3780905481.

It is an arithmetic number, because the mean of its divisors is an integer number (3780905481).

Almost surely, 2^7561810961 is an apocalyptic number.

It is an amenable number.

7561810961 is a deficient number, since it is larger than the sum of its proper divisors (1).

7561810961 is an equidigital number, since it uses as much as digits as its factorization.

7561810961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 90720, while the sum is 44.

The square root of 7561810961 is about 86958.6738686832. The cubic root of 7561810961 is about 1962.7964871866.

The spelling of 7561810961 in words is "seven billion, five hundred sixty-one million, eight hundred ten thousand, nine hundred sixty-one".