25664449 has 4 divisors (see below), whose sum is σ = 26549460. Its totient is φ = 24779440.

The previous prime is 25664437. The next prime is 25664453. The reversal of 25664449 is 94446652.

It is a happy number.

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 4870849 + 20793600 = 2207^2 + 4560^2 .

It is a cyclic number.

It is not a de Polignac number, because 25664449 - 2⁷ = 25664321 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25634449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 442462 + ... + 442519.

It is an arithmetic number, because the mean of its divisors is an integer number (6637365).

Almost surely, 2^25664449 is an apocalyptic number.

25664449 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

25664449 is a deficient number, since it is larger than the sum of its proper divisors (885011).

25664449 is an equidigital number, since it uses as much as digits as its factorization.

25664449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 885010.

The product of its digits is 207360, while the sum is 40.

The square root of 25664449 is about 5066.0091788310. The cubic root of 25664449 is about 294.9696377829.

The spelling of 25664449 in words is "twenty-five million, six hundred sixty-four thousand, four hundred forty-nine".