201331320021 has 12 divisors (see below), whose sum is σ = 313182053548. Its totient is φ = 123896196864.

The previous prime is 201331320011. The next prime is 201331320049. The reversal of 201331320021 is 120023133102.

It can be written as a sum of positive squares in 2 ways, for example, as 61088559921 + 140242760100 = 247161^2 + 374490^2 .

It is not a de Polignac number, because 201331320021 - 2¹¹ = 201331317973 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 201331319976 and 201331320003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201331320011) 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, 860390140 + ... + 860390373.

Almost surely, 2^201331320021 is an apocalyptic number.

It is an amenable number.

201331320021 is a deficient number, since it is larger than the sum of its proper divisors (111850733527).

201331320021 is a wasteful number, since it uses less digits than its factorization.

201331320021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1720780532 (or 1720780529 counting only the distinct ones).

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

Adding to 201331320021 its reverse (120023133102), we get a palindrome (321354453123).

The spelling of 201331320021 in words is "two hundred one billion, three hundred thirty-one million, three hundred twenty thousand, twenty-one".