25687421 has 8 divisors (see below), whose sum is σ = 26145504. Its totient is φ = 25233040.

The previous prime is 25687393. The next prime is 25687423. The reversal of 25687421 is 12478652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 25687421 - 2¹⁸ = 25425277 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 (25687423) 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 7 ways as a sum of consecutive naturals, for example, 15566 + ... + 17136.

It is an arithmetic number, because the mean of its divisors is an integer number (3268188).

Almost surely, 2^25687421 is an apocalyptic number.

It is an amenable number.

25687421 is a deficient number, since it is larger than the sum of its proper divisors (458083).

25687421 is a wasteful number, since it uses less digits than its factorization.

25687421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1851.

The product of its digits is 26880, while the sum is 35.

The square root of 25687421 is about 5068.2759396071. The cubic root of 25687421 is about 295.0576196939.

The spelling of 25687421 in words is "twenty-five million, six hundred eighty-seven thousand, four hundred twenty-one".