26728909 has 2 divisors, whose sum is σ = 26728910. Its totient is φ = 26728908.

The previous prime is 26728901. The next prime is 26728927. The reversal of 26728909 is 90982762.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26728900 + 9 = 5170^2 + 3^2 .

It is a cyclic number.

It is not a de Polignac number, because 26728909 - 2³ = 26728901 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26728901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13364454 + 13364455.

It is an arithmetic number, because the mean of its divisors is an integer number (13364455).

Almost surely, 2^26728909 is an apocalyptic number.

It is an amenable number.

26728909 is a deficient number, since it is larger than the sum of its proper divisors (1).

26728909 is an equidigital number, since it uses as much as digits as its factorization.

26728909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108864, while the sum is 43.

The square root of 26728909 is about 5170.0008704061. Note that the first 3 decimals coincide. The cubic root of 26728909 is about 298.9925800629.

The spelling of 26728909 in words is "twenty-six million, seven hundred twenty-eight thousand, nine hundred nine".