2021220101 has 4 divisors (see below), whose sum is σ = 2064224832. Its totient is φ = 1978215372.

The previous prime is 2021220079. The next prime is 2021220109. The reversal of 2021220101 is 1010221202.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2021220101 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 (2021220109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21502295 + ... + 21502388.

It is an arithmetic number, because the mean of its divisors is an integer number (516056208).

Almost surely, 2^2021220101 is an apocalyptic number.

It is an amenable number.

2021220101 is a deficient number, since it is larger than the sum of its proper divisors (43004731).

2021220101 is an equidigital number, since it uses as much as digits as its factorization.

2021220101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43004730.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 2021220101 is about 44957.9815049564. The cubic root of 2021220101 is about 1264.3613248673.

Adding to 2021220101 its reverse (1010221202), we get a palindrome (3031441303).

The spelling of 2021220101 in words is "two billion, twenty-one million, two hundred twenty thousand, one hundred one".