26921 has 2 divisors, whose sum is σ = 26922. Its totient is φ = 26920.

The previous prime is 26903. The next prime is 26927. The reversal of 26921 is 12962.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 26896 + 25 = 164^2 + 5^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-26921 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 26893 and 26902.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13460 + 13461.

It is an arithmetic number, because the mean of its divisors is an integer number (13461).

2²⁶⁹²¹ is an apocalyptic number.

It is an amenable number.

26921 is a deficient number, since it is larger than the sum of its proper divisors (1).

26921 is an equidigital number, since it uses as much as digits as its factorization.

26921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 216, while the sum is 20.

The square root of 26921 is about 164.0762018088. The cubic root of 26921 is about 29.9707121575.

The spelling of 26921 in words is "twenty-six thousand, nine hundred twenty-one".