1213128 has 96 divisors (see below), whose sum is σ = 3931200. Its totient is φ = 330624.

The previous prime is 1213109. The next prime is 1213129. The reversal of 1213128 is 8213121.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 1213128.

It is not an unprimeable number, because it can be changed into a prime (1213129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14575 + ... + 14657.

It is an arithmetic number, because the mean of its divisors is an integer number (40950).

2^1213128 is an apocalyptic number.

1213128 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1213128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1965600).

1213128 is an abundant number, since it is smaller than the sum of its proper divisors (2718072).

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

1213128 is a wasteful number, since it uses less digits than its factorization.

1213128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131 (or 124 counting only the distinct ones).

The product of its digits is 96, while the sum is 18.

The square root of 1213128 is about 1101.4209004736. The cubic root of 1213128 is about 106.6519684609.

Adding to 1213128 its reverse (8213121), we get a palindrome (9426249).

It can be divided in two parts, 121 and 3128, that added together give a square (3249 = 57²).

The spelling of 1213128 in words is "one million, two hundred thirteen thousand, one hundred twenty-eight".