15561464503493 has 2 divisors, whose sum is σ = 15561464503494. Its totient is φ = 15561464503492.

The previous prime is 15561464503463. The next prime is 15561464503513. The reversal of 15561464503493 is 39430546416551.

15561464503493 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15191652136609 + 369812366884 = 3897647^2 + 608122^2 .

It is a cyclic number.

It is not a de Polignac number, because 15561464503493 - 2⁸ = 15561464503237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15561464503433) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7780732251746 + 7780732251747.

It is an arithmetic number, because the mean of its divisors is an integer number (7780732251747).

Almost surely, 2^{15561464503493} is an apocalyptic number.

It is an amenable number.

15561464503493 is a deficient number, since it is larger than the sum of its proper divisors (1).

15561464503493 is an equidigital number, since it uses as much as digits as its factorization.

15561464503493 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328000, while the sum is 56.

The spelling of 15561464503493 in words is "fifteen trillion, five hundred sixty-one billion, four hundred sixty-four million, five hundred three thousand, four hundred ninety-three".