21242419 has 16 divisors (see below), whose sum is σ = 23950080. Its totient is φ = 18676000.

The previous prime is 21242393. The next prime is 21242443. The reversal of 21242419 is 91424212.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21242419 is a prime.

It is a super-2 number, since 2×21242419² = 902480729943122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21242393 and 21242402.

It is not an unprimeable number, because it can be changed into a prime (21242479) 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, 45849 + ... + 46309.

It is an arithmetic number, because the mean of its divisors is an integer number (1496880).

Almost surely, 2^21242419 is an apocalyptic number.

21242419 is a deficient number, since it is larger than the sum of its proper divisors (2707661).

21242419 is a wasteful number, since it uses less digits than its factorization.

21242419 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 602.

The product of its digits is 1152, while the sum is 25.

The square root of 21242419 is about 4608.9498803958. The cubic root of 21242419 is about 276.9499707637.

It can be divided in two parts, 2 and 1242419, that added together give a palindrome (1242421).

The spelling of 21242419 in words is "twenty-one million, two hundred forty-two thousand, four hundred nineteen".