26261581 has 2 divisors, whose sum is σ = 26261582. Its totient is φ = 26261580.

The previous prime is 26261569. The next prime is 26261611. The reversal of 26261581 is 18516262.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18139081 + 8122500 = 4259^2 + 2850^2 .

It is a cyclic number.

It is not a de Polignac number, because 26261581 - 2¹⁹ = 25737293 is a prime.

It is a super-2 number, since 2×26261581² = 1379341273239122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26261281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13130790 + 13130791.

It is an arithmetic number, because the mean of its divisors is an integer number (13130791).

Almost surely, 2^26261581 is an apocalyptic number.

It is an amenable number.

26261581 is a deficient number, since it is larger than the sum of its proper divisors (1).

26261581 is an equidigital number, since it uses as much as digits as its factorization.

26261581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5760, while the sum is 31.

The square root of 26261581 is about 5124.6054482272. The cubic root of 26261581 is about 297.2397969648.

The spelling of 26261581 in words is "twenty-six million, two hundred sixty-one thousand, five hundred eighty-one".