25641779 has 4 divisors (see below), whose sum is σ = 25895760. Its totient is φ = 25387800.

The previous prime is 25641751. The next prime is 25641793. The reversal of 25641779 is 97714652.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25641779 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25641709) 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, 126839 + ... + 127040.

It is an arithmetic number, because the mean of its divisors is an integer number (6473940).

Almost surely, 2^25641779 is an apocalyptic number.

25641779 is a deficient number, since it is larger than the sum of its proper divisors (253981).

25641779 is a wasteful number, since it uses less digits than its factorization.

25641779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253980.

The product of its digits is 105840, while the sum is 41.

The square root of 25641779 is about 5063.7712231103. The cubic root of 25641779 is about 294.8827610354.

The spelling of 25641779 in words is "twenty-five million, six hundred forty-one thousand, seven hundred seventy-nine".