1321221300209 has 4 divisors (see below), whose sum is σ = 1321796496804. Its totient is φ = 1320646103616.

The previous prime is 1321221300169. The next prime is 1321221300239. The reversal of 1321221300209 is 9020031221231.

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 194551566400 + 1126669733809 = 441080^2 + 1061447^2 .

It is a cyclic number.

It is not a de Polignac number, because 1321221300209 - 2³² = 1316926332913 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1321221300239) 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, 287594852 + ... + 287599445.

It is an arithmetic number, because the mean of its divisors is an integer number (330449124201).

Almost surely, 2^{1321221300209} is an apocalyptic number.

It is an amenable number.

1321221300209 is a deficient number, since it is larger than the sum of its proper divisors (575196595).

1321221300209 is an equidigital number, since it uses as much as digits as its factorization.

1321221300209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 575196594.

The product of its (nonzero) digits is 1296, while the sum is 26.

The spelling of 1321221300209 in words is "one trillion, three hundred twenty-one billion, two hundred twenty-one million, three hundred thousand, two hundred nine".