20256163 has 4 divisors (see below), whose sum is σ = 21447720. Its totient is φ = 19064608.

The previous prime is 20256161. The next prime is 20256217. The reversal of 20256163 is 36165202.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 36165202 = 2 ⋅18082601.

It is a cyclic number.

It is not a de Polignac number, because 20256163 - 2¹ = 20256161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20256161) 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, 595753 + ... + 595786.

It is an arithmetic number, because the mean of its divisors is an integer number (5361930).

Almost surely, 2^20256163 is an apocalyptic number.

20256163 is a deficient number, since it is larger than the sum of its proper divisors (1191557).

20256163 is a wasteful number, since it uses less digits than its factorization.

20256163 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1191556.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 20256163 is about 4500.6847256834. The cubic root of 20256163 is about 272.5957377601.

It can be divided in two parts, 202 and 56163, that added together give a palindrome (56365).

The spelling of 20256163 in words is "twenty million, two hundred fifty-six thousand, one hundred sixty-three".