21434245 has 8 divisors (see below), whose sum is σ = 29395584. Its totient is φ = 14697744.

The previous prime is 21434233. The next prime is 21434249. The reversal of 21434245 is 54243412.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21434245 - 2⁵ = 21434213 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 (21434249) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 306169 + ... + 306238.

It is an arithmetic number, because the mean of its divisors is an integer number (3674448).

Almost surely, 2^21434245 is an apocalyptic number.

It is an amenable number.

21434245 is a deficient number, since it is larger than the sum of its proper divisors (7961339).

21434245 is an equidigital number, since it uses as much as digits as its factorization.

21434245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 612419.

The product of its digits is 3840, while the sum is 25.

The square root of 21434245 is about 4629.7132740592. The cubic root of 21434245 is about 277.7811235449.

Adding to 21434245 its reverse (54243412), we get a palindrome (75677657).

The spelling of 21434245 in words is "twenty-one million, four hundred thirty-four thousand, two hundred forty-five".