21113263 has 8 divisors (see below), whose sum is σ = 21856256. Its totient is φ = 20374200.

The previous prime is 21113251. The next prime is 21113297. The reversal of 21113263 is 36231112.

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

It is a cyclic number.

It is not a de Polignac number, because 21113263 - 2⁵ = 21113231 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21113263.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21113243) 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, 13618 + ... + 15088.

It is an arithmetic number, because the mean of its divisors is an integer number (2732032).

Almost surely, 2^21113263 is an apocalyptic number.

21113263 is a deficient number, since it is larger than the sum of its proper divisors (742993).

21113263 is a wasteful number, since it uses less digits than its factorization.

21113263 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1965.

The product of its digits is 216, while the sum is 19.

The square root of 21113263 is about 4594.9170830386. The cubic root of 21113263 is about 276.3875349628.

Adding to 21113263 its reverse (36231112), we get a palindrome (57344375).

The spelling of 21113263 in words is "twenty-one million, one hundred thirteen thousand, two hundred sixty-three".