20102105511 has 24 divisors (see below), whose sum is σ = 29108439360. Its totient is φ = 13368194496.

The previous prime is 20102105509. The next prime is 20102105591. The reversal of 20102105511 is 11550120102.

20102105511 is a `hidden beast` number, since 2 + 0 + 102 + 10 + 551 + 1 = 666.

It is not a de Polignac number, because 20102105511 - 2¹ = 20102105509 is a prime.

It is a super-2 number, since 2×20102105511² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20102105591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8704825 + ... + 8707133.

It is an arithmetic number, because the mean of its divisors is an integer number (1212851640).

Almost surely, 2^20102105511 is an apocalyptic number.

20102105511 is a deficient number, since it is larger than the sum of its proper divisors (9006333849).

20102105511 is a wasteful number, since it uses less digits than its factorization.

20102105511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4295 (or 4292 counting only the distinct ones).

The product of its (nonzero) digits is 100, while the sum is 18.

Adding to 20102105511 its reverse (11550120102), we get a palindrome (31652225613).

The spelling of 20102105511 in words is "twenty billion, one hundred two million, one hundred five thousand, five hundred eleven".