1321980 has 48 divisors (see below), whose sum is σ = 4040064. Its totient is φ = 320320.

The previous prime is 1321961. The next prime is 1321981. The reversal of 1321980 is 891231.

1321980 = 403² + 404² + ... + 410².

It is a super-2 number, since 2×1321980² = 3495262240800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1321980.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321981) 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, 342 + ... + 1661.

It is an arithmetic number, because the mean of its divisors is an integer number (84168).

2^1321980 is an apocalyptic number.

1321980 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 1321980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2020032).

1321980 is an abundant number, since it is smaller than the sum of its proper divisors (2718084).

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

1321980 is a wasteful number, since it uses less digits than its factorization.

1321980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2026 (or 2024 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 24.

The square root of 1321980 is about 1149.7738908151. The cubic root of 1321980 is about 109.7509517130.

It can be divided in two parts, 132 and 1980, that added together give a palindrome (2112).

The spelling of 1321980 in words is "one million, three hundred twenty-one thousand, nine hundred eighty".