1213305 has 16 divisors (see below), whose sum is σ = 1983744. Its totient is φ = 632960.

The previous prime is 1213301. The next prime is 1213327. The reversal of 1213305 is 5033121.

It is a happy number.

It is not a de Polignac number, because 1213305 - 2² = 1213301 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is not an unprimeable number, because it can be changed into a prime (1213301) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 156 + ... + 1565.

It is an arithmetic number, because the mean of its divisors is an integer number (123984).

2^1213305 is an apocalyptic number.

1213305 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1213305 is a deficient number, since it is larger than the sum of its proper divisors (770439).

1213305 is a wasteful number, since it uses less digits than its factorization.

1213305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1776.

The product of its (nonzero) digits is 90, while the sum is 15.

The square root of 1213305 is about 1101.5012482971. The cubic root of 1213305 is about 106.6571551849.

Adding to 1213305 its reverse (5033121), we get a palindrome (6246426).

The spelling of 1213305 in words is "one million, two hundred thirteen thousand, three hundred five".