1312820 has 24 divisors (see below), whose sum is σ = 2825928. Its totient is φ = 512000.

The previous prime is 1312813. The next prime is 1312823. The reversal of 1312820 is 282131.

It can be written as a sum of positive squares in 4 ways, for example, as 206116 + 1106704 = 454^2 + 1052^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1312823) 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, 20 + ... + 1620.

It is an arithmetic number, because the mean of its divisors is an integer number (117747).

2^1312820 is an apocalyptic number.

1312820 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 1312820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1412964).

1312820 is an abundant number, since it is smaller than the sum of its proper divisors (1513108).

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

1312820 is a wasteful number, since it uses less digits than its factorization.

1312820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1651 (or 1649 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 1312820 is about 1145.7835746772. The cubic root of 1312820 is about 109.4968758448.

Adding to 1312820 its reverse (282131), we get a palindrome (1594951).

The spelling of 1312820 in words is "one million, three hundred twelve thousand, eight hundred twenty".