26561861 has 4 divisors (see below), whose sum is σ = 26572224. Its totient is φ = 26551500.

The previous prime is 26561833. The next prime is 26561863. The reversal of 26561861 is 16816562.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 26561861 - 2¹⁸ = 26299717 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26561863) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1796 + ... + 7506.

It is an arithmetic number, because the mean of its divisors is an integer number (6643056).

Almost surely, 2^26561861 is an apocalyptic number.

It is an amenable number.

26561861 is a deficient number, since it is larger than the sum of its proper divisors (10363).

26561861 is an equidigital number, since it uses as much as digits as its factorization.

26561861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10362.

The product of its digits is 17280, while the sum is 35.

The square root of 26561861 is about 5153.8200395435. The cubic root of 26561861 is about 298.3684053799.

It can be divided in two parts, 265 and 61861, that added together give a palindrome (62126).

The spelling of 26561861 in words is "twenty-six million, five hundred sixty-one thousand, eight hundred sixty-one".