21056163 has 8 divisors (see below), whose sum is σ = 28535376. Its totient is φ = 13807200.

The previous prime is 21056159. The next prime is 21056171. The reversal of 21056163 is 36165012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21056163 - 2² = 21056159 is a prime.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

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

It is not an unprimeable number, because it can be changed into a prime (21056143) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 57348 + ... + 57713.

It is an arithmetic number, because the mean of its divisors is an integer number (3566922).

Almost surely, 2^21056163 is an apocalyptic number.

21056163 is a deficient number, since it is larger than the sum of its proper divisors (7479213).

21056163 is a wasteful number, since it uses less digits than its factorization.

21056163 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115125.

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 21056163 is about 4588.6994889620. The cubic root of 21056163 is about 276.1381502248.

The spelling of 21056163 in words is "twenty-one million, fifty-six thousand, one hundred sixty-three".