11211100020 has 72 divisors (see below), whose sum is σ = 34123228776. Its totient is φ = 2979409152.

The previous prime is 11211100003. The next prime is 11211100031. The reversal of 11211100020 is 2000111211.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6602862564 + 4608237456 = 81258^2 + 67884^2 .

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 = 11211099975 and 11211100011.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 53547 + ... + 159026.

It is an arithmetic number, because the mean of its divisors is an integer number (473933733).

Almost surely, 2^11211100020 is an apocalyptic number.

11211100020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11211100020 is an abundant number, since it is smaller than the sum of its proper divisors (22912128756).

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

11211100020 is a wasteful number, since it uses less digits than its factorization.

11211100020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212881 (or 212876 counting only the distinct ones).

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

Adding to 11211100020 its reverse (2000111211), we get a palindrome (13211211231).

The spelling of 11211100020 in words is "eleven billion, two hundred eleven million, one hundred thousand, twenty".