1321220002 has 4 divisors (see below), whose sum is σ = 1981830006. Its totient is φ = 660610000.

The previous prime is 1321219997. The next prime is 1321220003. The reversal of 1321220002 is 2000221231.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 2000221231 = 1213 ⋅1648987.

It can be written as a sum of positive squares in only one way, i.e., 1173816121 + 147403881 = 34261^2 + 12141^2 .

It is not an unprimeable number, because it can be changed into a prime (1321220003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330304999 + ... + 330305002.

Almost surely, 2^1321220002 is an apocalyptic number.

1321220002 is a deficient number, since it is larger than the sum of its proper divisors (660610004).

1321220002 is an equidigital number, since it uses as much as digits as its factorization.

1321220002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660610003.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 1321220002 is about 36348.5900964535. The cubic root of 1321220002 is about 1097.2991597038.

Adding to 1321220002 its reverse (2000221231), we get a palindrome (3321441233).

The spelling of 1321220002 in words is "one billion, three hundred twenty-one million, two hundred twenty thousand, two".