21284453 has 8 divisors (see below), whose sum is σ = 22752576. Its totient is φ = 19861600.

The previous prime is 21284423. The next prime is 21284489. The reversal of 21284453 is 35448212.

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 a de Polignac number, because none of the positive numbers 2^k-21284453 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 (21284423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10343 + ... + 12228.

It is an arithmetic number, because the mean of its divisors is an integer number (2844072).

Almost surely, 2^21284453 is an apocalyptic number.

21284453 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21284453 is a deficient number, since it is larger than the sum of its proper divisors (1468123).

21284453 is a wasteful number, since it uses less digits than its factorization.

21284453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22635.

The product of its digits is 7680, while the sum is 29.

The square root of 21284453 is about 4613.5076677079. The cubic root of 21284453 is about 277.1325244390.

The spelling of 21284453 in words is "twenty-one million, two hundred eighty-four thousand, four hundred fifty-three".