25816643 has 4 divisors (see below), whose sum is σ = 25924008. Its totient is φ = 25709280.

The previous prime is 25816631. The next prime is 25816657. The reversal of 25816643 is 34661852.

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 25816643 - 2⁴ = 25816627 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25816613) 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, 53321 + ... + 53802.

It is an arithmetic number, because the mean of its divisors is an integer number (6481002).

Almost surely, 2^25816643 is an apocalyptic number.

25816643 is a deficient number, since it is larger than the sum of its proper divisors (107365).

25816643 is a wasteful number, since it uses less digits than its factorization.

25816643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107364.

The product of its digits is 34560, while the sum is 35.

The square root of 25816643 is about 5081.0080692713. The cubic root of 25816643 is about 295.5515602743.

The spelling of 25816643 in words is "twenty-five million, eight hundred sixteen thousand, six hundred forty-three".