21413263 has 4 divisors (see below), whose sum is σ = 21442528. Its totient is φ = 21384000.

The previous prime is 21413243. The next prime is 21413279. The reversal of 21413263 is 36231412.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21413263 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21413243) 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, 13506 + ... + 15007.

It is an arithmetic number, because the mean of its divisors is an integer number (5360632).

Almost surely, 2^21413263 is an apocalyptic number.

21413263 is a deficient number, since it is larger than the sum of its proper divisors (29265).

21413263 is an equidigital number, since it uses as much as digits as its factorization.

21413263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29264.

The product of its digits is 864, while the sum is 22.

The square root of 21413263 is about 4627.4467041772. The cubic root of 21413263 is about 277.6904538964.

Adding to 21413263 its reverse (36231412), we get a palindrome (57644675).

The spelling of 21413263 in words is "twenty-one million, four hundred thirteen thousand, two hundred sixty-three".