25421861 has 4 divisors (see below), whose sum is σ = 25852800. Its totient is φ = 24990924.

The previous prime is 25421839. The next prime is 25421899. The reversal of 25421861 is 16812452.

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 25421861 - 2⁶ = 25421797 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 (25421161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 215381 + ... + 215498.

It is an arithmetic number, because the mean of its divisors is an integer number (6463200).

Almost surely, 2^25421861 is an apocalyptic number.

It is an amenable number.

25421861 is a deficient number, since it is larger than the sum of its proper divisors (430939).

25421861 is an equidigital number, since it uses as much as digits as its factorization.

25421861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 430938.

The product of its digits is 3840, while the sum is 29.

The square root of 25421861 is about 5042.0096191896. The cubic root of 25421861 is about 294.0373138196.

The spelling of 25421861 in words is "twenty-five million, four hundred twenty-one thousand, eight hundred sixty-one".