20111211221100 has 72 divisors (see below), whose sum is σ = 58191152069568. Its totient is φ = 5362739496000.

The previous prime is 20111211221081. The next prime is 20111211221113. The reversal of 20111211221100 is 112211211102.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 20111211221100.

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, 4923375 + ... + 8028825.

Almost surely, 2^{20111211221100} is an apocalyptic number.

20111211221100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20111211221100 is an abundant number, since it is smaller than the sum of its proper divisors (38079940848468).

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

20111211221100 is a wasteful number, since it uses less digits than its factorization.

20111211221100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3127055 (or 3127048 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 20111211221100 its reverse (112211211102), we get a palindrome (20223422432202).

The spelling of 20111211221100 in words is "twenty trillion, one hundred eleven billion, two hundred eleven million, two hundred twenty-one thousand, one hundred".