2021021021111 has 4 divisors (see below), whose sum is σ = 2021025611112. Its totient is φ = 2021016431112.

The previous prime is 2021021021099. The next prime is 2021021021137. The reversal of 2021021021111 is 1111201201202.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2021021021111 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2021021021011) 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, 1555001 + ... + 2541666.

It is an arithmetic number, because the mean of its divisors is an integer number (505256402778).

Almost surely, 2^{2021021021111} is an apocalyptic number.

2021021021111 is a deficient number, since it is larger than the sum of its proper divisors (4590001).

2021021021111 is an equidigital number, since it uses as much as digits as its factorization.

2021021021111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4590000.

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

Adding to 2021021021111 its reverse (1111201201202), we get a palindrome (3132222222313).

The spelling of 2021021021111 in words is "two trillion, twenty-one billion, twenty-one million, twenty-one thousand, one hundred eleven".