25821853 has 4 divisors (see below), whose sum is σ = 26654848. Its totient is φ = 24988860.

The previous prime is 25821833. The next prime is 25821857. The reversal of 25821853 is 35812852.

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 25821853 - 2⁵ = 25821821 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25821857) 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, 416451 + ... + 416512.

It is an arithmetic number, because the mean of its divisors is an integer number (6663712).

Almost surely, 2^25821853 is an apocalyptic number.

It is an amenable number.

25821853 is a deficient number, since it is larger than the sum of its proper divisors (832995).

25821853 is an equidigital number, since it uses as much as digits as its factorization.

25821853 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 832994.

The product of its digits is 19200, while the sum is 34.

The square root of 25821853 is about 5081.5207369448. The cubic root of 25821853 is about 295.5714404741.

Subtracting 25821853 from its reverse (35812852), we obtain a palindrome (9990999).

The spelling of 25821853 in words is "twenty-five million, eight hundred twenty-one thousand, eight hundred fifty-three".