21411243 has 16 divisors (see below), whose sum is σ = 36252160. Its totient is φ = 12234888.

The previous prime is 21411241. The next prime is 21411253. The reversal of 21411243 is 34211412.

It is not a de Polignac number, because 21411243 - 2¹ = 21411241 is a prime.

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (21411241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 56455 + ... + 56832.

It is an arithmetic number, because the mean of its divisors is an integer number (2265760).

Almost surely, 2^21411243 is an apocalyptic number.

21411243 is a deficient number, since it is larger than the sum of its proper divisors (14840917).

21411243 is a wasteful number, since it uses less digits than its factorization.

21411243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113303 (or 113297 counting only the distinct ones).

The product of its digits is 192, while the sum is 18.

The square root of 21411243 is about 4627.2284361159. The cubic root of 21411243 is about 277.6817217327.

Adding to 21411243 its reverse (34211412), we get a palindrome (55622655).

The spelling of 21411243 in words is "twenty-one million, four hundred eleven thousand, two hundred forty-three".