21563153 has 8 divisors (see below), whose sum is σ = 22526400. Its totient is φ = 20614608.

The previous prime is 21563149. The next prime is 21563161. The reversal of 21563153 is 35136512.

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 21563153 - 2² = 21563149 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21563173) 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, 623 + ... + 6596.

It is an arithmetic number, because the mean of its divisors is an integer number (2815800).

Almost surely, 2^21563153 is an apocalyptic number.

It is an amenable number.

21563153 is a deficient number, since it is larger than the sum of its proper divisors (963247).

21563153 is a wasteful number, since it uses less digits than its factorization.

21563153 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7351.

The product of its digits is 2700, while the sum is 26.

The square root of 21563153 is about 4643.6142173958. The cubic root of 21563153 is about 278.3368800469.

Adding to 21563153 its reverse (35136512), we get a palindrome (56699665).

The spelling of 21563153 in words is "twenty-one million, five hundred sixty-three thousand, one hundred fifty-three".