25287421 has 2 divisors, whose sum is σ = 25287422. Its totient is φ = 25287420.

The previous prime is 25287403. The next prime is 25287433. The reversal of 25287421 is 12478252.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14976900 + 10310521 = 3870^2 + 3211^2 .

It is a cyclic number.

It is not a de Polignac number, because 25287421 - 2⁵ = 25287389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25267421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12643710 + 12643711.

It is an arithmetic number, because the mean of its divisors is an integer number (12643711).

Almost surely, 2^25287421 is an apocalyptic number.

It is an amenable number.

25287421 is a deficient number, since it is larger than the sum of its proper divisors (1).

25287421 is an equidigital number, since it uses as much as digits as its factorization.

25287421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8960, while the sum is 31.

The square root of 25287421 is about 5028.6599606655. The cubic root of 25287421 is about 293.5180721904.

The spelling of 25287421 in words is "twenty-five million, two hundred eighty-seven thousand, four hundred twenty-one".