1211230312021 has 2 divisors, whose sum is σ = 1211230312022. Its totient is φ = 1211230312020.

The previous prime is 1211230311931. The next prime is 1211230312031. The reversal of 1211230312021 is 1202130321121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 701490002500 + 509740309521 = 837550^2 + 713961^2 .

It is an emirp because it is prime and its reverse (1202130321121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1211230312021 - 2⁹ = 1211230311509 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1211230312021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211230312031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605615156010 + 605615156011.

It is an arithmetic number, because the mean of its divisors is an integer number (605615156011).

Almost surely, 2^{1211230312021} is an apocalyptic number.

It is an amenable number.

1211230312021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211230312021 is an equidigital number, since it uses as much as digits as its factorization.

1211230312021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 1211230312021 its reverse (1202130321121), we get a palindrome (2413360633142).

It can be divided in two parts, 12112303 and 12021, that added together give a square (12124324 = 3482²).

The spelling of 1211230312021 in words is "one trillion, two hundred eleven billion, two hundred thirty million, three hundred twelve thousand, twenty-one".