20011111021 has 8 divisors (see below), whose sum is σ = 21880724544. Its totient is φ = 18149901120.

The previous prime is 20011111013. The next prime is 20011111031. The reversal of 20011111021 is 12011111002.

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 20011111021 - 2³ = 20011111013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20011110989 and 20011111007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20011111031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2095921 + ... + 2105446.

It is an arithmetic number, because the mean of its divisors is an integer number (2735090568).

Almost surely, 2^20011111021 is an apocalyptic number.

It is an amenable number.

20011111021 is a deficient number, since it is larger than the sum of its proper divisors (1869613523).

20011111021 is a wasteful number, since it uses less digits than its factorization.

20011111021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4201811.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 20011111021 its reverse (12011111002), we get a palindrome (32022222023).

The spelling of 20011111021 in words is "twenty billion, eleven million, one hundred eleven thousand, twenty-one".