15651116066561 has 2 divisors, whose sum is σ = 15651116066562. Its totient is φ = 15651116066560.

The previous prime is 15651116066503. The next prime is 15651116066629. The reversal of 15651116066561 is 16566061115651.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11719941433600 + 3931174632961 = 3423440^2 + 1982719^2 .

It is a cyclic number.

It is not a de Polignac number, because 15651116066561 - 2¹⁰ = 15651116065537 is a prime.

It is not a weakly prime, because it can be changed into another prime (15651116066161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7825558033280 + 7825558033281.

It is an arithmetic number, because the mean of its divisors is an integer number (7825558033281).

Almost surely, 2^{15651116066561} is an apocalyptic number.

It is an amenable number.

15651116066561 is a deficient number, since it is larger than the sum of its proper divisors (1).

15651116066561 is an equidigital number, since it uses as much as digits as its factorization.

15651116066561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972000, while the sum is 50.

The spelling of 15651116066561 in words is "fifteen trillion, six hundred fifty-one billion, one hundred sixteen million, sixty-six thousand, five hundred sixty-one".