7661667007609 has 2 divisors, whose sum is σ = 7661667007610. Its totient is φ = 7661667007608.

The previous prime is 7661667007567. The next prime is 7661667007717. The reversal of 7661667007609 is 9067007661667.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7660318281984 + 1348725625 = 2767728^2 + 36725^2 .

It is a cyclic number.

It is not a de Polignac number, because 7661667007609 - 2³⁷ = 7524228054137 is a prime.

It is a super-2 number, since 2×7661667007609² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (7661667007909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3830833503804 + 3830833503805.

It is an arithmetic number, because the mean of its divisors is an integer number (3830833503805).

Almost surely, 2^{7661667007609} is an apocalyptic number.

It is an amenable number.

7661667007609 is a deficient number, since it is larger than the sum of its proper divisors (1).

7661667007609 is an equidigital number, since it uses as much as digits as its factorization.

7661667007609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24004512, while the sum is 61.

The spelling of 7661667007609 in words is "seven trillion, six hundred sixty-one billion, six hundred sixty-seven million, seven thousand, six hundred nine".