20101211111 has 8 divisors (see below), whose sum is σ = 21632548464. Its totient is φ = 18608641920.

The previous prime is 20101211107. The next prime is 20101211167. The reversal of 20101211111 is 11111210102.

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 20101211111 - 2² = 20101211107 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20101211092 and 20101211101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20101211311) 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, 9690965 + ... + 9693038.

It is an arithmetic number, because the mean of its divisors is an integer number (2704068558).

Almost surely, 2^20101211111 is an apocalyptic number.

20101211111 is a deficient number, since it is larger than the sum of its proper divisors (1531337353).

20101211111 is a wasteful number, since it uses less digits than its factorization.

20101211111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19384081.

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 20101211111 its reverse (11111210102), we get a palindrome (31212421213).

It can be divided in two parts, 2010 and 1211111, that added together give a palindrome (1213121).

The spelling of 20101211111 in words is "twenty billion, one hundred one million, two hundred eleven thousand, one hundred eleven".