15761661217 has 2 divisors, whose sum is σ = 15761661218. Its totient is φ = 15761661216.

The previous prime is 15761661193. The next prime is 15761661257. The reversal of 15761661217 is 71216616751.

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., 15731179776 + 30481441 = 125424^2 + 5521^2 .

It is a cyclic number.

It is not a de Polignac number, because 15761661217 - 2⁷ = 15761661089 is a prime.

It is not a weakly prime, because it can be changed into another prime (15761661257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7880830608 + 7880830609.

It is an arithmetic number, because the mean of its divisors is an integer number (7880830609).

Almost surely, 2^15761661217 is an apocalyptic number.

It is an amenable number.

15761661217 is a deficient number, since it is larger than the sum of its proper divisors (1).

15761661217 is an equidigital number, since it uses as much as digits as its factorization.

15761661217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 105840, while the sum is 43.

The spelling of 15761661217 in words is "fifteen billion, seven hundred sixty-one million, six hundred sixty-one thousand, two hundred seventeen".