21456193 has 16 divisors (see below), whose sum is σ = 24960960. Its totient is φ = 18227200.

The previous prime is 21456191. The next prime is 21456199. The reversal of 21456193 is 39165412.

It is a cyclic number.

It is not a de Polignac number, because 21456193 - 2¹ = 21456191 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21456191) 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 15 ways as a sum of consecutive naturals, for example, 33153 + ... + 33793.

It is an arithmetic number, because the mean of its divisors is an integer number (1560060).

Almost surely, 2^21456193 is an apocalyptic number.

It is an amenable number.

21456193 is a deficient number, since it is larger than the sum of its proper divisors (3504767).

21456193 is a wasteful number, since it uses less digits than its factorization.

21456193 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 848.

The product of its digits is 6480, while the sum is 31.

The square root of 21456193 is about 4632.0830087553. The cubic root of 21456193 is about 277.8759042774.

It can be divided in two parts, 2145 and 6193, that added together give a palindrome (8338).

The spelling of 21456193 in words is "twenty-one million, four hundred fifty-six thousand, one hundred ninety-three".