1221202021201 has 2 divisors, whose sum is σ = 1221202021202. Its totient is φ = 1221202021200.

The previous prime is 1221202021183. The next prime is 1221202021271. The reversal of 1221202021201 is 1021202021221.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1048791051025 + 172410970176 = 1024105^2 + 415224^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221202021201 - 2¹⁹ = 1221201496913 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221202021271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610601010600 + 610601010601.

It is an arithmetic number, because the mean of its divisors is an integer number (610601010601).

Almost surely, 2^{1221202021201} is an apocalyptic number.

It is an amenable number.

1221202021201 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221202021201 is an equidigital number, since it uses as much as digits as its factorization.

1221202021201 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 1221202021201 its reverse (1021202021221), we get a palindrome (2242404042422).

It can be divided in two parts, 12212020 and 21201, that added together give a palindrome (12233221).

The spelling of 1221202021201 in words is "one trillion, two hundred twenty-one billion, two hundred two million, twenty-one thousand, two hundred one".