25804781 has 4 divisors (see below), whose sum is σ = 26926752. Its totient is φ = 24682812.

The previous prime is 25804777. The next prime is 25804811. The reversal of 25804781 is 18740852.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 25804781 - 2² = 25804777 is a prime.

It is a super-2 number, since 2×25804781² = 1331773444915922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25804721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 560951 + ... + 560996.

It is an arithmetic number, because the mean of its divisors is an integer number (6731688).

Almost surely, 2^25804781 is an apocalyptic number.

It is an amenable number.

25804781 is a deficient number, since it is larger than the sum of its proper divisors (1121971).

25804781 is a wasteful number, since it uses less digits than its factorization.

25804781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1121970.

The product of its (nonzero) digits is 17920, while the sum is 35.

The square root of 25804781 is about 5079.8406471070. The cubic root of 25804781 is about 295.5062875448.

The spelling of 25804781 in words is "twenty-five million, eight hundred four thousand, seven hundred eighty-one".