26561821 has 8 divisors (see below), whose sum is σ = 31205664. Its totient is φ = 22289520.

The previous prime is 26561789. The next prime is 26561827. The reversal of 26561821 is 12816562.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 26561821 - 2⁵ = 26561789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26561827) 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 in 7 ways as a sum of consecutive naturals, for example, 92731 + ... + 93016.

It is an arithmetic number, because the mean of its divisors is an integer number (3900708).

Almost surely, 2^26561821 is an apocalyptic number.

It is an amenable number.

26561821 is a deficient number, since it is larger than the sum of its proper divisors (4643843).

26561821 is a wasteful number, since it uses less digits than its factorization.

26561821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185771.

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

The square root of 26561821 is about 5153.8161589253. The cubic root of 26561821 is about 298.3682556070.

The spelling of 26561821 in words is "twenty-six million, five hundred sixty-one thousand, eight hundred twenty-one".