1213728 has 48 divisors (see below), whose sum is σ = 3265920. Its totient is φ = 394496.

The previous prime is 1213721. The next prime is 1213741. The reversal of 1213728 is 8273121.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a junction number, because it is equal to n+sod(n) for n = 1213698 and 1213707.

It is not an unprimeable number, because it can be changed into a prime (1213721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4378 + ... + 4646.

It is an arithmetic number, because the mean of its divisors is an integer number (68040).

2^1213728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1213728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1632960).

1213728 is an abundant number, since it is smaller than the sum of its proper divisors (2052192).

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

1213728 is a wasteful number, since it uses less digits than its factorization.

1213728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 329 (or 321 counting only the distinct ones).

The product of its digits is 672, while the sum is 24.

The square root of 1213728 is about 1101.6932422412. The cubic root of 1213728 is about 106.6695485332.

Adding to 1213728 its reverse (8273121), we get a palindrome (9486849).

The spelling of 1213728 in words is "one million, two hundred thirteen thousand, seven hundred twenty-eight".