2021010111221 has 2 divisors, whose sum is σ = 2021010111222. Its totient is φ = 2021010111220.

The previous prime is 2021010111187. The next prime is 2021010111277. The reversal of 2021010111221 is 1221110101202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1764883023121 + 256127088100 = 1328489^2 + 506090^2 .

It is a cyclic number.

It is not a de Polignac number, because 2021010111221 - 2³⁸ = 1746132204277 is a prime.

It is a super-2 number, since 2×2021010111221² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 2021010111196 and 2021010111205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2021010111521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1010505055610 + 1010505055611.

It is an arithmetic number, because the mean of its divisors is an integer number (1010505055611).

Almost surely, 2^{2021010111221} is an apocalyptic number.

It is an amenable number.

2021010111221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2021010111221 is an equidigital number, since it uses as much as digits as its factorization.

2021010111221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 2021010111221 its reverse (1221110101202), we get a palindrome (3242120212423).

The spelling of 2021010111221 in words is "two trillion, twenty-one billion, ten million, one hundred eleven thousand, two hundred twenty-one".