2021111993 has 8 divisors (see below), whose sum is σ = 2098948680. Its totient is φ = 1943818240.

The previous prime is 2021111971. The next prime is 2021111999. The reversal of 2021111993 is 3991111202.

It can be written as a sum of positive squares in 4 ways, for example, as 1269639424 + 751472569 = 35632^2 + 27413^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2021111993 - 2¹⁰ = 2021110969 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2021111999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 128138 + ... + 143043.

It is an arithmetic number, because the mean of its divisors is an integer number (262368585).

Almost surely, 2^2021111993 is an apocalyptic number.

It is an amenable number.

2021111993 is a deficient number, since it is larger than the sum of its proper divisors (77836687).

2021111993 is a wasteful number, since it uses less digits than its factorization.

2021111993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 271467.

The product of its (nonzero) digits is 972, while the sum is 29.

The square root of 2021111993 is about 44956.7791662170. The cubic root of 2021111993 is about 1264.3387823758.

It can be divided in two parts, 202111199 and 3, that added together give a palindrome (202111202).

The spelling of 2021111993 in words is "two billion, twenty-one million, one hundred eleven thousand, nine hundred ninety-three".