15561044459 has 2 divisors, whose sum is σ = 15561044460. Its totient is φ = 15561044458.

The previous prime is 15561044449. The next prime is 15561044501. The reversal of 15561044459 is 95444016551.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 15561044459 - 2⁸ = 15561044203 is a prime.

It is a super-2 number, since 2×15561044459² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (15561044419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7780522229 + 7780522230.

It is an arithmetic number, because the mean of its divisors is an integer number (7780522230).

Almost surely, 2^15561044459 is an apocalyptic number.

15561044459 is a deficient number, since it is larger than the sum of its proper divisors (1).

15561044459 is an equidigital number, since it uses as much as digits as its factorization.

15561044459 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432000, while the sum is 44.

The spelling of 15561044459 in words is "fifteen billion, five hundred sixty-one million, forty-four thousand, four hundred fifty-nine".