1216563 has 4 divisors (see below), whose sum is σ = 1622088. Its totient is φ = 811040.

The previous prime is 1216561. The next prime is 1216577. The reversal of 1216563 is 3656121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1216563 - 2¹ = 1216561 is a prime.

It is a D-number.

It is an alternating number because its digits alternate between odd and even.

1216563 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1216561) 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, 202758 + ... + 202763.

It is an arithmetic number, because the mean of its divisors is an integer number (405522).

2^1216563 is an apocalyptic number.

1216563 is a deficient number, since it is larger than the sum of its proper divisors (405525).

1216563 is an equidigital number, since it uses as much as digits as its factorization.

1216563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 405524.

The product of its digits is 1080, while the sum is 24.

The square root of 1216563 is about 1102.9791475817. The cubic root of 1216563 is about 106.7525361061.

The spelling of 1216563 in words is "one million, two hundred sixteen thousand, five hundred sixty-three".