1331032221 has 12 divisors (see below), whose sum is σ = 2035696572. Its totient is φ = 835157376.

The previous prime is 1331032207. The next prime is 1331032231. The reversal of 1331032221 is 1222301331.

1331032221 is a `hidden beast` number, since 13 + 310 + 322 + 21 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 490844025 + 840188196 = 22155^2 + 28986^2 .

It is not a de Polignac number, because 1331032221 - 2⁷ = 1331032093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1331032194 and 1331032203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1331032201) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4349626 + ... + 4349931.

It is an arithmetic number, because the mean of its divisors is an integer number (169641381).

Almost surely, 2^1331032221 is an apocalyptic number.

It is an amenable number.

1331032221 is a deficient number, since it is larger than the sum of its proper divisors (704664351).

1331032221 is a wasteful number, since it uses less digits than its factorization.

1331032221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8699580 (or 8699577 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 1331032221 is about 36483.3142820112. The cubic root of 1331032221 is about 1100.0088762369.

Adding to 1331032221 its reverse (1222301331), we get a palindrome (2553333552).

The spelling of 1331032221 in words is "one billion, three hundred thirty-one million, thirty-two thousand, two hundred twenty-one".