26278661 has 2 divisors, whose sum is σ = 26278662. Its totient is φ = 26278660.

The previous prime is 26278643. The next prime is 26278667. The reversal of 26278661 is 16687262.

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., 25502500 + 776161 = 5050^2 + 881^2 .

It is a cyclic number.

It is not a de Polignac number, because 26278661 - 2⁶ = 26278597 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 (26278667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13139330 + 13139331.

It is an arithmetic number, because the mean of its divisors is an integer number (13139331).

Almost surely, 2^26278661 is an apocalyptic number.

It is an amenable number.

26278661 is a deficient number, since it is larger than the sum of its proper divisors (1).

26278661 is an equidigital number, since it uses as much as digits as its factorization.

26278661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48384, while the sum is 38.

The square root of 26278661 is about 5126.2716471135. The cubic root of 26278661 is about 297.3042225796.

The spelling of 26278661 in words is "twenty-six million, two hundred seventy-eight thousand, six hundred sixty-one".