1331200021 has 16 divisors (see below), whose sum is σ = 1454875200. Its totient is φ = 1213204608.

The previous prime is 1331200009. The next prime is 1331200027. The reversal of 1331200021 is 1200021331.

It is a cyclic number.

It is not a de Polignac number, because 1331200021 - 2⁷ = 1331199893 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1331199974 and 1331200010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1331200027) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 151665 + ... + 160201.

It is an arithmetic number, because the mean of its divisors is an integer number (90929700).

Almost surely, 2^1331200021 is an apocalyptic number.

It is an amenable number.

1331200021 is a deficient number, since it is larger than the sum of its proper divisors (123675179).

1331200021 is a wasteful number, since it uses less digits than its factorization.

1331200021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8868.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 1331200021 is about 36485.6138909571. The cubic root of 1331200021 is about 1100.0550994439.

Adding to 1331200021 its reverse (1200021331), we get a palindrome (2531221352).

The spelling of 1331200021 in words is "one billion, three hundred thirty-one million, two hundred thousand, twenty-one".