16252561561 has 4 divisors (see below), whose sum is σ = 17208594612. Its totient is φ = 15296528512.

The previous prime is 16252561547. The next prime is 16252561571. The reversal of 16252561561 is 16516525261.

16252561561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4545321561 + 11707240000 = 67419^2 + 108200^2 .

It is a cyclic number.

It is not a de Polignac number, because 16252561561 - 2²³ = 16244172953 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16252561531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 478016500 + ... + 478016533.

It is an arithmetic number, because the mean of its divisors is an integer number (4302148653).

Almost surely, 2^16252561561 is an apocalyptic number.

It is an amenable number.

16252561561 is a deficient number, since it is larger than the sum of its proper divisors (956033051).

16252561561 is an equidigital number, since it uses as much as digits as its factorization.

16252561561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 956033050.

The product of its digits is 108000, while the sum is 40.

The spelling of 16252561561 in words is "sixteen billion, two hundred fifty-two million, five hundred sixty-one thousand, five hundred sixty-one".