1211020021201 has 12 divisors (see below), whose sum is σ = 1248159582900. Its totient is φ = 1174917861600.

The previous prime is 1211020021193. The next prime is 1211020021219. The reversal of 1211020021201 is 1021200201121.

It can be written as a sum of positive squares in 2 ways, for example, as 67566204225 + 1143453816976 = 259935^2 + 1069324^2 .

It is not a de Polignac number, because 1211020021201 - 2³ = 1211020021193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1211020021301) 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, 1922350 + ... + 2473351.

It is an arithmetic number, because the mean of its divisors is an integer number (104013298575).

Almost surely, 2^{1211020021201} is an apocalyptic number.

It is an amenable number.

1211020021201 is a deficient number, since it is larger than the sum of its proper divisors (37139561699).

1211020021201 is an equidigital number, since it uses as much as digits as its factorization.

1211020021201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4395936 (or 4395893 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 1211020021201 its reverse (1021200201121), we get a palindrome (2232220222322).

The spelling of 1211020021201 in words is "one trillion, two hundred eleven billion, twenty million, twenty-one thousand, two hundred one".