21434219 has 4 divisors (see below), whose sum is σ = 22173360. Its totient is φ = 20695080.

The previous prime is 21434213. The next prime is 21434221. The reversal of 21434219 is 91243412.

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-21434219 is a prime.

It is a super-2 number, since 2×21434219² = 918851488279922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21434213) 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, 369527 + ... + 369584.

It is an arithmetic number, because the mean of its divisors is an integer number (5543340).

Almost surely, 2^21434219 is an apocalyptic number.

21434219 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

21434219 is a deficient number, since it is larger than the sum of its proper divisors (739141).

21434219 is an equidigital number, since it uses as much as digits as its factorization.

21434219 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 739140.

The product of its digits is 1728, while the sum is 26.

The square root of 21434219 is about 4629.7104661091. The cubic root of 21434219 is about 277.7810112275.

The spelling of 21434219 in words is "twenty-one million, four hundred thirty-four thousand, two hundred nineteen".