1215863 has 4 divisors (see below), whose sum is σ = 1326408. Its totient is φ = 1105320.

The previous prime is 1215859. The next prime is 1215881. The reversal of 1215863 is 3685121.

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 1215863 - 2² = 1215859 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 (1215853) 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, 55256 + ... + 55277.

It is an arithmetic number, because the mean of its divisors is an integer number (331602).

2^1215863 is an apocalyptic number.

1215863 is a deficient number, since it is larger than the sum of its proper divisors (110545).

1215863 is a wasteful number, since it uses less digits than its factorization.

1215863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110544.

The product of its digits is 1440, while the sum is 26.

The square root of 1215863 is about 1102.6617795136. The cubic root of 1215863 is about 106.7320573441.

It can be divided in two parts, 12158 and 63, that added together give a palindrome (12221).

The spelling of 1215863 in words is "one million, two hundred fifteen thousand, eight hundred sixty-three".