2021011999 has 4 divisors (see below), whose sum is σ = 2021121160. Its totient is φ = 2020902840.

The previous prime is 2021011981. The next prime is 2021012009. The reversal of 2021011999 is 9991101202.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 2021011999 - 2¹¹ = 2021009951 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 (2021012999) 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, 19137 + ... + 66394.

It is an arithmetic number, because the mean of its divisors is an integer number (505280290).

Almost surely, 2^2021011999 is an apocalyptic number.

2021011999 is a deficient number, since it is larger than the sum of its proper divisors (109161).

2021011999 is an equidigital number, since it uses as much as digits as its factorization.

2021011999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109160.

The product of its (nonzero) digits is 2916, while the sum is 34.

The square root of 2021011999 is about 44955.6670398738. The cubic root of 2021011999 is about 1264.3179310857.

The spelling of 2021011999 in words is "two billion, twenty-one million, eleven thousand, nine hundred ninety-nine".