20021111 has 8 divisors (see below), whose sum is σ = 21982224. Its totient is φ = 18083520.

The previous prime is 20021093. The next prime is 20021137. The reversal of 20021111 is 11112002.

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 20021111 - 2¹⁴ = 20004727 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20021171) 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 7 ways as a sum of consecutive naturals, for example, 4070 + ... + 7523.

It is an arithmetic number, because the mean of its divisors is an integer number (2747778).

Almost surely, 2^20021111 is an apocalyptic number.

20021111 is a deficient number, since it is larger than the sum of its proper divisors (1961113).

20021111 is a wasteful number, since it uses less digits than its factorization.

20021111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11761.

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 20021111 is about 4474.4956140329. The cubic root of 20021111 is about 271.5372348590.

Adding to 20021111 its reverse (11112002), we get a palindrome (31133113).

It can be divided in two parts, 2002 and 1111, that multiplied together give a palindrome (2224222).

The spelling of 20021111 in words is "twenty million, twenty-one thousand, one hundred eleven".