1331001221 has 8 divisors (see below), whose sum is σ = 1452417888. Its totient is φ = 1209654000.

The previous prime is 1331001187. The next prime is 1331001223. The reversal of 1331001221 is 1221001331.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1331001221 - 2¹⁰ = 1331000197 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1331001196 and 1331001205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1331001223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27851 + ... + 58631.

It is an arithmetic number, because the mean of its divisors is an integer number (181552236).

Almost surely, 2^1331001221 is an apocalyptic number.

1331001221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1331001221 is a deficient number, since it is larger than the sum of its proper divisors (121416667).

1331001221 is a wasteful number, since it uses less digits than its factorization.

1331001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34723.

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 1331001221 is about 36482.8894277852. The cubic root of 1331001221 is about 1100.0003363635. Note that the first 3 decimals are identical.

Adding to 1331001221 its reverse (1221001331), we get a palindrome (2552002552).

The spelling of 1331001221 in words is "one billion, three hundred thirty-one million, one thousand, two hundred twenty-one".