21356341 has 2 divisors, whose sum is σ = 21356342. Its totient is φ = 21356340.

The previous prime is 21356339. The next prime is 21356347. The reversal of 21356341 is 14365312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17255716 + 4100625 = 4154^2 + 2025^2 .

It is a cyclic number.

It is not a de Polignac number, because 21356341 - 2¹ = 21356339 is a prime.

Together with 21356339, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21356347) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10678170 + 10678171.

It is an arithmetic number, because the mean of its divisors is an integer number (10678171).

Almost surely, 2^21356341 is an apocalyptic number.

It is an amenable number.

21356341 is a deficient number, since it is larger than the sum of its proper divisors (1).

21356341 is an equidigital number, since it uses as much as digits as its factorization.

21356341 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2160, while the sum is 25.

The square root of 21356341 is about 4621.2921353232. The cubic root of 21356341 is about 277.4441778254. Note that the first 3 decimals are identical.

The spelling of 21356341 in words is "twenty-one million, three hundred fifty-six thousand, three hundred forty-one".