20101111020 has 72 divisors (see below), whose sum is σ = 61658513280. Its totient is φ = 5300064000.

The previous prime is 20101111007. The next prime is 20101111031. The reversal of 20101111020 is 2011110102.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 20101110993 and 20101111011.

It is an unprimeable number.

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, 611356 + ... + 643395.

It is an arithmetic number, because the mean of its divisors is an integer number (856368240).

Almost surely, 2^20101111020 is an apocalyptic number.

20101111020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20101111020 is an abundant number, since it is smaller than the sum of its proper divisors (41557402260).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20101111020 is a wasteful number, since it uses less digits than its factorization.

20101111020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1254855 (or 1254850 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 20101111020 its reverse (2011110102), we get a palindrome (22112221122).

The spelling of 20101111020 in words is "twenty billion, one hundred one million, one hundred eleven thousand, twenty".