20012021111 has 4 divisors (see below), whose sum is σ = 21065285400. Its totient is φ = 18958756824.

The previous prime is 20012021093. The next prime is 20012021129. The reversal of 20012021111 is 11112021002.

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

It is an interprime number because it is at equal distance from previous prime (20012021093) and next prime (20012021129).

It is a cyclic number.

It is not a de Polignac number, because 20012021111 - 2⁶ = 20012021047 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20012021092 and 20012021101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20012021131) 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, 526632116 + ... + 526632153.

It is an arithmetic number, because the mean of its divisors is an integer number (5266321350).

Almost surely, 2^20012021111 is an apocalyptic number.

20012021111 is a deficient number, since it is larger than the sum of its proper divisors (1053264289).

20012021111 is a wasteful number, since it uses less digits than its factorization.

20012021111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1053264288.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 20012021111 its reverse (11112021002), we get a palindrome (31124042113).

The spelling of 20012021111 in words is "twenty billion, twelve million, twenty-one thousand, one hundred eleven".