25606816447 has 4 divisors (see below), whose sum is σ = 26432842816. Its totient is φ = 24780790080.

The previous prime is 25606816441. The next prime is 25606816451. The reversal of 25606816447 is 74461860652.

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

It is a cyclic number.

It is not a de Polignac number, because 25606816447 - 2²⁷ = 25472598719 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 25606816447.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25606816441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 413013138 + ... + 413013199.

It is an arithmetic number, because the mean of its divisors is an integer number (6608210704).

Almost surely, 2^25606816447 is an apocalyptic number.

25606816447 is a deficient number, since it is larger than the sum of its proper divisors (826026369).

25606816447 is an equidigital number, since it uses as much as digits as its factorization.

25606816447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 826026368.

The product of its (nonzero) digits is 1935360, while the sum is 49.

The spelling of 25606816447 in words is "twenty-five billion, six hundred six million, eight hundred sixteen thousand, four hundred forty-seven".