2021210121001 has 4 divisors (see below), whose sum is σ = 2021513931972. Its totient is φ = 2020906310032.

The previous prime is 2021210120987. The next prime is 2021210121011. The reversal of 2021210121001 is 1001210121202.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 207137855376 + 1814072265625 = 455124^2 + 1346875^2 .

It is a cyclic number.

It is not a de Polignac number, because 2021210121001 - 2⁷ = 2021210120873 is a prime.

It is a super-2 number, since 2×2021210121001² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2021210121011) 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, 151895506 + ... + 151908811.

It is an arithmetic number, because the mean of its divisors is an integer number (505378482993).

Almost surely, 2^{2021210121001} is an apocalyptic number.

It is an amenable number.

2021210121001 is a deficient number, since it is larger than the sum of its proper divisors (303810971).

2021210121001 is an equidigital number, since it uses as much as digits as its factorization.

2021210121001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 303810970.

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

Adding to 2021210121001 its reverse (1001210121202), we get a palindrome (3022420242203).

The spelling of 2021210121001 in words is "two trillion, twenty-one billion, two hundred ten million, one hundred twenty-one thousand, one".