21052163 has 4 divisors (see below), whose sum is σ = 22966008. Its totient is φ = 19138320.

The previous prime is 21052159. The next prime is 21052169. The reversal of 21052163 is 36125012.

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 21052163 - 2² = 21052159 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21052169) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 956906 + ... + 956927.

It is an arithmetic number, because the mean of its divisors is an integer number (5741502).

Almost surely, 2^21052163 is an apocalyptic number.

21052163 is a deficient number, since it is larger than the sum of its proper divisors (1913845).

21052163 is a wasteful number, since it uses less digits than its factorization.

21052163 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1913844.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 21052163 is about 4588.2636149201. The cubic root of 21052163 is about 276.1206633011.

Adding to 21052163 its reverse (36125012), we get a palindrome (57177175).

It can be divided in two parts, 2 and 1052163, that multiplied together give a triangular number (2104326 = T₂₀₅₁).

The spelling of 21052163 in words is "twenty-one million, fifty-two thousand, one hundred sixty-three".