26890309 has 2 divisors, whose sum is σ = 26890310. Its totient is φ = 26890308.

The previous prime is 26890307. The next prime is 26890319. The reversal of 26890309 is 90309862.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26884225 + 6084 = 5185^2 + 78^2 .

It is a cyclic number.

It is not a de Polignac number, because 26890309 - 2¹ = 26890307 is a prime.

Together with 26890307, 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 (26890307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13445154 + 13445155.

It is an arithmetic number, because the mean of its divisors is an integer number (13445155).

Almost surely, 2^26890309 is an apocalyptic number.

It is an amenable number.

26890309 is a deficient number, since it is larger than the sum of its proper divisors (1).

26890309 is an equidigital number, since it uses as much as digits as its factorization.

26890309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 26890309 is about 5185.5866591930. The cubic root of 26890309 is about 299.5931856266.

The spelling of 26890309 in words is "twenty-six million, eight hundred ninety thousand, three hundred nine".