1320521 has 4 divisors (see below), whose sum is σ = 1325700. Its totient is φ = 1315344.

The previous prime is 1320437. The next prime is 1320533. The reversal of 1320521 is 1250231.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 774400 + 546121 = 880^2 + 739^2 .

It is a cyclic number.

It is not a de Polignac number, because 1320521 - 2¹⁴ = 1304137 is a prime.

It is a super-2 number, since 2×1320521² = 3487551422882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1320496 and 1320505.

It is not an unprimeable number, because it can be changed into a prime (1320541) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2186 + ... + 2723.

It is an arithmetic number, because the mean of its divisors is an integer number (331425).

2^1320521 is an apocalyptic number.

It is an amenable number.

1320521 is a deficient number, since it is larger than the sum of its proper divisors (5179).

1320521 is an equidigital number, since it uses as much as digits as its factorization.

1320521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5178.

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 1320521 is about 1149.1392430859. The cubic root of 1320521 is about 109.7105613938.

Adding to 1320521 its reverse (1250231), we get a palindrome (2570752).

The spelling of 1320521 in words is "one million, three hundred twenty thousand, five hundred twenty-one".