21367393 has 2 divisors, whose sum is σ = 21367394. Its totient is φ = 21367392.

The previous prime is 21367331. The next prime is 21367397. The reversal of 21367393 is 39376312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11235904 + 10131489 = 3352^2 + 3183^2 .

It is a cyclic number.

It is not a de Polignac number, because 21367393 - 2¹³ = 21359201 is a prime.

It is not a weakly prime, because it can be changed into another prime (21367397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10683696 + 10683697.

It is an arithmetic number, because the mean of its divisors is an integer number (10683697).

Almost surely, 2^21367393 is an apocalyptic number.

It is an amenable number.

21367393 is a deficient number, since it is larger than the sum of its proper divisors (1).

21367393 is an equidigital number, since it uses as much as digits as its factorization.

21367393 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20412, while the sum is 34.

The square root of 21367393 is about 4622.4877501190. The cubic root of 21367393 is about 277.4920290977.

The spelling of 21367393 in words is "twenty-one million, three hundred sixty-seven thousand, three hundred ninety-three".