25781219 has 2 divisors, whose sum is σ = 25781220. Its totient is φ = 25781218.

The previous prime is 25781213. The next prime is 25781227. The reversal of 25781219 is 91218752.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25781219 is a prime.

It is a super-2 number, since 2×25781219² = 1329342506251922, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (25781213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12890609 + 12890610.

It is an arithmetic number, because the mean of its divisors is an integer number (12890610).

Almost surely, 2^25781219 is an apocalyptic number.

25781219 is a deficient number, since it is larger than the sum of its proper divisors (1).

25781219 is an equidigital number, since it uses as much as digits as its factorization.

25781219 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10080, while the sum is 35.

The square root of 25781219 is about 5077.5209502276. The cubic root of 25781219 is about 295.4163192115.

The spelling of 25781219 in words is "twenty-five million, seven hundred eighty-one thousand, two hundred nineteen".