7637405561 has 2 divisors, whose sum is σ = 7637405562. Its totient is φ = 7637405560.

The previous prime is 7637405549. The next prime is 7637405563. The reversal of 7637405561 is 1655047367.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7582926400 + 54479161 = 87080^2 + 7381^2 .

It is a cyclic number.

It is not a de Polignac number, because 7637405561 - 2³⁰ = 6563663737 is a prime.

Together with 7637405563, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (7637405563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3818702780 + 3818702781.

It is an arithmetic number, because the mean of its divisors is an integer number (3818702781).

Almost surely, 2^7637405561 is an apocalyptic number.

It is an amenable number.

7637405561 is a deficient number, since it is larger than the sum of its proper divisors (1).

7637405561 is an equidigital number, since it uses as much as digits as its factorization.

7637405561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 529200, while the sum is 44.

The square root of 7637405561 is about 87392.2511496300. The cubic root of 7637405561 is about 1969.3154329928.

The spelling of 7637405561 in words is "seven billion, six hundred thirty-seven million, four hundred five thousand, five hundred sixty-one".