25780409 has 2 divisors, whose sum is σ = 25780410. Its totient is φ = 25780408.

The previous prime is 25780367. The next prime is 25780411. The reversal of 25780409 is 90408752.

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., 25725184 + 55225 = 5072^2 + 235^2 .

It is a cyclic number.

It is not a de Polignac number, because 25780409 - 2¹² = 25776313 is a prime.

It is a super-3 number, since 3×25780409³ (a number of 23 digits) contains 333 as substring.

Together with 25780411, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (25780429) by changing a digit.

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

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12890204 + 12890205.

It is an arithmetic number, because the mean of its divisors is an integer number (12890205).

Almost surely, 2^25780409 is an apocalyptic number.

It is an amenable number.

25780409 is a deficient number, since it is larger than the sum of its proper divisors (1).

25780409 is an equidigital number, since it uses as much as digits as its factorization.

25780409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20160, while the sum is 35.

The square root of 25780409 is about 5077.4411862670. The cubic root of 25780409 is about 295.4132253609.

The spelling of 25780409 in words is "twenty-five million, seven hundred eighty thousand, four hundred nine".