21110393 has 2 divisors, whose sum is σ = 21110394. Its totient is φ = 21110392.

The previous prime is 21110381. The next prime is 21110423. The reversal of 21110393 is 39301112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20457529 + 652864 = 4523^2 + 808^2 .

It is a cyclic number.

It is not a de Polignac number, because 21110393 - 2¹⁰ = 21109369 is a prime.

It is a super-2 number, since 2×21110393² = 891297385228898, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21110363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555196 + 10555197.

It is an arithmetic number, because the mean of its divisors is an integer number (10555197).

Almost surely, 2^21110393 is an apocalyptic number.

It is an amenable number.

21110393 is a deficient number, since it is larger than the sum of its proper divisors (1).

21110393 is an equidigital number, since it uses as much as digits as its factorization.

21110393 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 20.

The square root of 21110393 is about 4594.6047708154. The cubic root of 21110393 is about 276.3750109525.

The spelling of 21110393 in words is "twenty-one million, one hundred ten thousand, three hundred ninety-three".