201211231310021 has 4 divisors (see below), whose sum is σ = 201214745912544. Its totient is φ = 201207716707500.

The previous prime is 201211231310017. The next prime is 201211231310051. The reversal of 201211231310021 is 120013132112102.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 201211231310021 - 2² = 201211231310017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 201211231309975 and 201211231310002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201211231310051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1757215385 + ... + 1757329886.

It is an arithmetic number, because the mean of its divisors is an integer number (50303686478136).

Almost surely, 2^{201211231310021} is an apocalyptic number.

It is an amenable number.

201211231310021 is a deficient number, since it is larger than the sum of its proper divisors (3514602523).

201211231310021 is an equidigital number, since it uses as much as digits as its factorization.

201211231310021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3514602522.

The product of its (nonzero) digits is 144, while the sum is 20.

Adding to 201211231310021 its reverse (120013132112102), we get a palindrome (321224363422123).

The spelling of 201211231310021 in words is "two hundred one trillion, two hundred eleven billion, two hundred thirty-one million, three hundred ten thousand, twenty-one".