1231320 has 64 divisors (see below), whose sum is σ = 3824640. Its totient is φ = 316800.

The previous prime is 1231319. The next prime is 1231337. The reversal of 1231320 is 231321.

It is a happy number.

It is a super-2 number, since 2×1231320² = 3032297884800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a zygodrome in base 11.

It is a junction number, because it is equal to n+sod(n) for n = 1231296 and 1231305.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3555 + ... + 3885.

It is an arithmetic number, because the mean of its divisors is an integer number (59760).

2^1231320 is an apocalyptic number.

1231320 is a gapful number since it is divisible by the number (10) 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 1231320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1912320).

1231320 is an abundant number, since it is smaller than the sum of its proper divisors (2593320).

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

1231320 is a wasteful number, since it uses less digits than its factorization.

1231320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 376 (or 372 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 1231320 is about 1109.6485930239. The cubic root of 1231320 is about 107.1824412468.

Adding to 1231320 its reverse (231321), we get a palindrome (1462641).

Subtracting from 1231320 its reverse (231321), we obtain a palindrome (999999).

It can be divided in two parts, 1231 and 320, that added together give a palindrome (1551).

The spelling of 1231320 in words is "one million, two hundred thirty-one thousand, three hundred twenty".