15934243866509 has 2 divisors, whose sum is σ = 15934243866510. Its totient is φ = 15934243866508.

The previous prime is 15934243866503. The next prime is 15934243866577. The reversal of 15934243866509 is 90566834243951.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14753972388100 + 1180271478409 = 3841090^2 + 1086403^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15934243866509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15934243866503) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7967121933254 + 7967121933255.

It is an arithmetic number, because the mean of its divisors is an integer number (7967121933255).

Almost surely, 2^{15934243866509} is an apocalyptic number.

It is an amenable number.

15934243866509 is a deficient number, since it is larger than the sum of its proper divisors (1).

15934243866509 is an equidigital number, since it uses as much as digits as its factorization.

15934243866509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 167961600, while the sum is 65.

The spelling of 15934243866509 in words is "fifteen trillion, nine hundred thirty-four billion, two hundred forty-three million, eight hundred sixty-six thousand, five hundred nine".