20021211021111 has 16 divisors (see below), whose sum is σ = 26845497893760. Its totient is φ = 13272215916960.

The previous prime is 20021211021059. The next prime is 20021211021113. The reversal of 20021211021111 is 11112011212002.

It is a happy number.

It is not a de Polignac number, because 20021211021111 - 2²³ = 20021202632503 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20021211021113) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2667016 + ... + 6866978.

It is an arithmetic number, because the mean of its divisors is an integer number (1677843618360).

Almost surely, 2^{20021211021111} is an apocalyptic number.

20021211021111 is a deficient number, since it is larger than the sum of its proper divisors (6824286872649).

20021211021111 is a wasteful number, since it uses less digits than its factorization.

20021211021111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4208926.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 20021211021111 its reverse (11112011212002), we get a palindrome (31133222233113).

The spelling of 20021211021111 in words is "twenty trillion, twenty-one billion, two hundred eleven million, twenty-one thousand, one hundred eleven".