25770221 has 2 divisors, whose sum is σ = 25770222. Its totient is φ = 25770220.

The previous prime is 25770191. The next prime is 25770233. The reversal of 25770221 is 12207752.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13060996 + 12709225 = 3614^2 + 3565^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25770221 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25770721) 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, 12885110 + 12885111.

It is an arithmetic number, because the mean of its divisors is an integer number (12885111).

Almost surely, 2^25770221 is an apocalyptic number.

It is an amenable number.

25770221 is a deficient number, since it is larger than the sum of its proper divisors (1).

25770221 is an equidigital number, since it uses as much as digits as its factorization.

25770221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1960, while the sum is 26.

The square root of 25770221 is about 5076.4378258775. The cubic root of 25770221 is about 295.3743060600.

Adding to 25770221 its reverse (12207752), we get a palindrome (37977973).

The spelling of 25770221 in words is "twenty-five million, seven hundred seventy thousand, two hundred twenty-one".