25256421 has 8 divisors (see below), whose sum is σ = 37416960. Its totient is φ = 16837596.

The previous prime is 25256383. The next prime is 25256431. The reversal of 25256421 is 12465252.

It is not a de Polignac number, because 25256421 - 2¹⁰ = 25255397 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 935423 = 25256421 / (2 + 5 + 2 + 5 + 6 + 4 + 2 + 1).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25256431) 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 7 ways as a sum of consecutive naturals, for example, 467685 + ... + 467738.

It is an arithmetic number, because the mean of its divisors is an integer number (4677120).

Almost surely, 2^25256421 is an apocalyptic number.

It is an amenable number.

25256421 is a deficient number, since it is larger than the sum of its proper divisors (12160539).

25256421 is an equidigital number, since it uses as much as digits as its factorization.

25256421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 935432 (or 935426 counting only the distinct ones).

The product of its digits is 4800, while the sum is 27.

The square root of 25256421 is about 5025.5766833270. The cubic root of 25256421 is about 293.3980812936.

The spelling of 25256421 in words is "twenty-five million, two hundred fifty-six thousand, four hundred twenty-one".