21867263 has 16 divisors (see below), whose sum is σ = 24748416. Its totient is φ = 19148640.

The previous prime is 21867221. The next prime is 21867277. The reversal of 21867263 is 36276812.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21867263 - 2¹⁰ = 21866239 is a prime.

It is a super-2 number, since 2×21867263² = 956354382222338, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21860263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38981 + ... + 39537.

It is an arithmetic number, because the mean of its divisors is an integer number (1546776).

Almost surely, 2^21867263 is an apocalyptic number.

21867263 is a deficient number, since it is larger than the sum of its proper divisors (2881153).

21867263 is a wasteful number, since it uses less digits than its factorization.

21867263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 694.

The product of its digits is 24192, while the sum is 35.

The square root of 21867263 is about 4676.2445402267. The cubic root of 21867263 is about 279.6392590747.

It can be divided in two parts, 2186 and 7263, that added together give a palindrome (9449).

The spelling of 21867263 in words is "twenty-one million, eight hundred sixty-seven thousand, two hundred sixty-three".