1320322021 has 4 divisors (see below), whose sum is σ = 1321870732. Its totient is φ = 1318773312.

The previous prime is 1320322013. The next prime is 1320322039. The reversal of 1320322021 is 1202230231.

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 306600100 + 1013721921 = 17510^2 + 31839^2 .

It is a cyclic number.

It is not a de Polignac number, because 1320322021 - 2³ = 1320322013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1320321986 and 1320322004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1320352021) 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, 773076 + ... + 774781.

It is an arithmetic number, because the mean of its divisors is an integer number (330467683).

Almost surely, 2^1320322021 is an apocalyptic number.

It is an amenable number.

1320322021 is a deficient number, since it is larger than the sum of its proper divisors (1548711).

1320322021 is an equidigital number, since it uses as much as digits as its factorization.

1320322021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1548710.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 1320322021 is about 36336.2356470782. The cubic root of 1320322021 is about 1097.0505064099.

Adding to 1320322021 its reverse (1202230231), we get a palindrome (2522552252).

The spelling of 1320322021 in words is "one billion, three hundred twenty million, three hundred twenty-two thousand, twenty-one".