25609691 has 4 divisors (see below), whose sum is σ = 26029584. Its totient is φ = 25189800.

The previous prime is 25609687. The next prime is 25609723. The reversal of 25609691 is 19690652.

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 25609691 - 2² = 25609687 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25609621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 209855 + ... + 209976.

It is an arithmetic number, because the mean of its divisors is an integer number (6507396).

Almost surely, 2^25609691 is an apocalyptic number.

25609691 is a deficient number, since it is larger than the sum of its proper divisors (419893).

25609691 is an equidigital number, since it uses as much as digits as its factorization.

25609691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 419892.

The product of its (nonzero) digits is 29160, while the sum is 38.

The square root of 25609691 is about 5060.6018416785. The cubic root of 25609691 is about 294.7597047299.

The spelling of 25609691 in words is "twenty-five million, six hundred nine thousand, six hundred ninety-one".