1215563 has 4 divisors (see below), whose sum is σ = 1279560. Its totient is φ = 1151568.

The previous prime is 1215553. The next prime is 1215569. The reversal of 1215563 is 3655121.

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 1215563 - 2⁶ = 1215499 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215569) 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, 31970 + ... + 32007.

It is an arithmetic number, because the mean of its divisors is an integer number (319890).

2^1215563 is an apocalyptic number.

1215563 is a deficient number, since it is larger than the sum of its proper divisors (63997).

1215563 is an equidigital number, since it uses as much as digits as its factorization.

1215563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63996.

The product of its digits is 900, while the sum is 23.

The square root of 1215563 is about 1102.5257366611. The cubic root of 1215563 is about 106.7232783257.

The spelling of 1215563 in words is "one million, two hundred fifteen thousand, five hundred sixty-three".