26291389 has 2 divisors, whose sum is σ = 26291390. Its totient is φ = 26291388.

The previous prime is 26291387. The next prime is 26291393. The reversal of 26291389 is 98319262.

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., 26163225 + 128164 = 5115^2 + 358^2 .

It is a cyclic number.

It is not a de Polignac number, because 26291389 - 2¹ = 26291387 is a prime.

Together with 26291387, 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 (26291381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13145694 + 13145695.

It is an arithmetic number, because the mean of its divisors is an integer number (13145695).

Almost surely, 2^26291389 is an apocalyptic number.

It is an amenable number.

26291389 is a deficient number, since it is larger than the sum of its proper divisors (1).

26291389 is an equidigital number, since it uses as much as digits as its factorization.

26291389 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 40.

The square root of 26291389 is about 5127.5129448886. The cubic root of 26291389 is about 297.3522143370.

The spelling of 26291389 in words is "twenty-six million, two hundred ninety-one thousand, three hundred eighty-nine".