25616665 has 8 divisors (see below), whose sum is σ = 30767688. Its totient is φ = 20474880.

The previous prime is 25616653. The next prime is 25616681. The reversal of 25616665 is 56661652.

It can be written as a sum of positive squares in 4 ways, for example, as 1054729 + 24561936 = 1027^2 + 4956^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-25616665 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7929 + ... + 10681.

It is an arithmetic number, because the mean of its divisors is an integer number (3845961).

Almost surely, 2^25616665 is an apocalyptic number.

It is an amenable number.

25616665 is a deficient number, since it is larger than the sum of its proper divisors (5151023).

25616665 is a wasteful number, since it uses less digits than its factorization.

25616665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4619.

The product of its digits is 64800, while the sum is 37.

The square root of 25616665 is about 5061.2908432533. The cubic root of 25616665 is about 294.7864585034.

The spelling of 25616665 in words is "twenty-five million, six hundred sixteen thousand, six hundred sixty-five".