1215828 has 18 divisors (see below), whose sum is σ = 3073434. Its totient is φ = 405264.

The previous prime is 1215827. The next prime is 1215839. The reversal of 1215828 is 8285121.

It can be written as a sum of positive squares in only one way, i.e., 1077444 + 138384 = 1038^2 + 372^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215827) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 16851 + ... + 16922.

2^1215828 is an apocalyptic number.

1215828 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1215828 is an abundant number, since it is smaller than the sum of its proper divisors (1857606).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1215828 is a wasteful number, since it uses less digits than its factorization.

1215828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33783 (or 33778 counting only the distinct ones).

The product of its digits is 1280, while the sum is 27.

The square root of 1215828 is about 1102.6459087123. The cubic root of 1215828 is about 106.7310331997.

The spelling of 1215828 in words is "one million, two hundred fifteen thousand, eight hundred twenty-eight".