21417241 has 4 divisors (see below), whose sum is σ = 21487312. Its totient is φ = 21347172.

The previous prime is 21417239. The next prime is 21417257. The reversal of 21417241 is 14271412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21417241 - 2¹ = 21417239 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21417271) 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, 34575 + ... + 35188.

It is an arithmetic number, because the mean of its divisors is an integer number (5371828).

Almost surely, 2^21417241 is an apocalyptic number.

It is an amenable number.

21417241 is a deficient number, since it is larger than the sum of its proper divisors (70071).

21417241 is an equidigital number, since it uses as much as digits as its factorization.

21417241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70070.

The product of its digits is 448, while the sum is 22.

The square root of 21417241 is about 4627.8765108849. The cubic root of 21417241 is about 277.7076486015.

Adding to 21417241 its reverse (14271412), we get a palindrome (35688653).

The spelling of 21417241 in words is "twenty-one million, four hundred seventeen thousand, two hundred forty-one".