15216163663661 has 2 divisors, whose sum is σ = 15216163663662. Its totient is φ = 15216163663660.

The previous prime is 15216163663639. The next prime is 15216163663703. The reversal of 15216163663661 is 16636636161251.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15117438253225 + 98725410436 = 3888115^2 + 314206^2 .

It is a cyclic number.

It is not a de Polignac number, because 15216163663661 - 2²⁶ = 15216096554797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15216163633661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7608081831830 + 7608081831831.

It is an arithmetic number, because the mean of its divisors is an integer number (7608081831831).

Almost surely, 2^{15216163663661} is an apocalyptic number.

It is an amenable number.

15216163663661 is a deficient number, since it is larger than the sum of its proper divisors (1).

15216163663661 is an equidigital number, since it uses as much as digits as its factorization.

15216163663661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4199040, while the sum is 53.

The spelling of 15216163663661 in words is "fifteen trillion, two hundred sixteen billion, one hundred sixty-three million, six hundred sixty-three thousand, six hundred sixty-one".