26661289 has 2 divisors, whose sum is σ = 26661290. Its totient is φ = 26661288.

The previous prime is 26661259. The next prime is 26661293. The reversal of 26661289 is 98216662.

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., 26347689 + 313600 = 5133^2 + 560^2 .

It is a cyclic number.

It is not a de Polignac number, because 26661289 - 2¹⁵ = 26628521 is a prime.

It is a super-2 number, since 2×26661289² = 1421648662283042, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (26661259) 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, 13330644 + 13330645.

It is an arithmetic number, because the mean of its divisors is an integer number (13330645).

Almost surely, 2^26661289 is an apocalyptic number.

It is an amenable number.

26661289 is a deficient number, since it is larger than the sum of its proper divisors (1).

26661289 is an equidigital number, since it uses as much as digits as its factorization.

26661289 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 62208, while the sum is 40.

The square root of 26661289 is about 5163.4570783536. The cubic root of 26661289 is about 298.7402321696.

The spelling of 26661289 in words is "twenty-six million, six hundred sixty-one thousand, two hundred eighty-nine".