26538781 has 2 divisors, whose sum is σ = 26538782. Its totient is φ = 26538780.

The previous prime is 26538779. The next prime is 26538829. The reversal of 26538781 is 18783562.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26429881 + 108900 = 5141^2 + 330^2 .

It is a cyclic number.

It is not a de Polignac number, because 26538781 - 2¹ = 26538779 is a prime.

It is a super-2 number, since 2×26538781² = 1408613793931922, which contains 22 as substring.

Together with 26538779, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26538761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13269390 + 13269391.

It is an arithmetic number, because the mean of its divisors is an integer number (13269391).

Almost surely, 2^26538781 is an apocalyptic number.

It is an amenable number.

26538781 is a deficient number, since it is larger than the sum of its proper divisors (1).

26538781 is an equidigital number, since it uses as much as digits as its factorization.

26538781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 80640, while the sum is 40.

The square root of 26538781 is about 5151.5804371086. The cubic root of 26538781 is about 298.2819614078.

The spelling of 26538781 in words is "twenty-six million, five hundred thirty-eight thousand, seven hundred eighty-one".