21363193 has 2 divisors, whose sum is σ = 21363194. Its totient is φ = 21363192.

The previous prime is 21363191. The next prime is 21363253. The reversal of 21363193 is 39136312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21040569 + 322624 = 4587^2 + 568^2 .

It is a cyclic number.

It is not a de Polignac number, because 21363193 - 2¹ = 21363191 is a prime.

Together with 21363191, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21363191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10681596 + 10681597.

It is an arithmetic number, because the mean of its divisors is an integer number (10681597).

Almost surely, 2^21363193 is an apocalyptic number.

It is an amenable number.

21363193 is a deficient number, since it is larger than the sum of its proper divisors (1).

21363193 is an equidigital number, since it uses as much as digits as its factorization.

21363193 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2916, while the sum is 28.

The square root of 21363193 is about 4622.0334269670. The cubic root of 21363193 is about 277.4738465193.

It can be divided in two parts, 2136 and 3193, that added together give a square (5329 = 73²).

The spelling of 21363193 in words is "twenty-one million, three hundred sixty-three thousand, one hundred ninety-three".