20010121111 has 16 divisors (see below), whose sum is σ = 21319313760. Its totient is φ = 18727372800.

The previous prime is 20010121097. The next prime is 20010121129. The reversal of 20010121111 is 11112101002.

It is not a de Polignac number, because 20010121111 - 2⁷ = 20010120983 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 (20010121171) 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, 865575 + ... + 888391.

It is an arithmetic number, because the mean of its divisors is an integer number (1332457110).

Almost surely, 2^20010121111 is an apocalyptic number.

20010121111 is a deficient number, since it is larger than the sum of its proper divisors (1309192649).

20010121111 is a wasteful number, since it uses less digits than its factorization.

20010121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23394.

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

Adding to 20010121111 its reverse (11112101002), we get a palindrome (31122222113).

The spelling of 20010121111 in words is "twenty billion, ten million, one hundred twenty-one thousand, one hundred eleven".