1320001221 has 48 divisors (see below), whose sum is σ = 2225172992. Its totient is φ = 681294240.

The previous prime is 1320001213. The next prime is 1320001223. The reversal of 1320001221 is 1221000231.

It is not a de Polignac number, because 1320001221 - 2³ = 1320001213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1320001197 and 1320001206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1320001223) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 412590 + ... + 415776.

Almost surely, 2^1320001221 is an apocalyptic number.

1320001221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1320001221 is a deficient number, since it is larger than the sum of its proper divisors (905171771).

1320001221 is a wasteful number, since it uses less digits than its factorization.

1320001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3382 (or 3371 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 1320001221 is about 36331.8210526255. The cubic root of 1320001221 is about 1096.9616487162.

Adding to 1320001221 its reverse (1221000231), we get a palindrome (2541001452).

The spelling of 1320001221 in words is "one billion, three hundred twenty million, one thousand, two hundred twenty-one".