26540221 has 2 divisors, whose sum is σ = 26540222. Its totient is φ = 26540220.

The previous prime is 26540219. The next prime is 26540237. The reversal of 26540221 is 12204562.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26163225 + 376996 = 5115^2 + 614^2 .

It is a cyclic number.

It is not a de Polignac number, because 26540221 - 2¹ = 26540219 is a prime.

Together with 26540219, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 26540192 and 26540201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26540291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13270110 + 13270111.

It is an arithmetic number, because the mean of its divisors is an integer number (13270111).

Almost surely, 2^26540221 is an apocalyptic number.

It is an amenable number.

26540221 is a deficient number, since it is larger than the sum of its proper divisors (1).

26540221 is an equidigital number, since it uses as much as digits as its factorization.

26540221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 26540221 is about 5151.7201981474. The cubic root of 26540221 is about 298.2873562582.

Adding to 26540221 its reverse (12204562), we get a palindrome (38744783).

The spelling of 26540221 in words is "twenty-six million, five hundred forty thousand, two hundred twenty-one".