21163019 has 4 divisors (see below), whose sum is σ = 21613344. Its totient is φ = 20712696.

The previous prime is 21163003. The next prime is 21163033. The reversal of 21163019 is 91036112.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21163019 - 2⁴ = 21163003 is a prime.

It is a super-2 number, since 2×21163019² = 895746746388722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21162985 and 21163003.

It is not an unprimeable number, because it can be changed into a prime (21163099) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 225092 + ... + 225185.

It is an arithmetic number, because the mean of its divisors is an integer number (5403336).

Almost surely, 2^21163019 is an apocalyptic number.

21163019 is a deficient number, since it is larger than the sum of its proper divisors (450325).

21163019 is an equidigital number, since it uses as much as digits as its factorization.

21163019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 450324.

The product of its (nonzero) digits is 324, while the sum is 23.

The square root of 21163019 is about 4600.3281404700. The cubic root of 21163019 is about 276.6044783694.

The spelling of 21163019 in words is "twenty-one million, one hundred sixty-three thousand, nineteen".