111001002100020 has 72 divisors (see below), whose sum is σ = 336704672443776. Its totient is φ = 29600123689152.

The previous prime is 111001002100003. The next prime is 111001002100057. The reversal of 111001002100020 is 20001200100111.

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 = 111001002099975 and 111001002100011.

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, 38724369 + ... + 41491911.

Almost surely, 2^{111001002100020} is an apocalyptic number.

111001002100020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

111001002100020 is an abundant number, since it is smaller than the sum of its proper divisors (225703670343756).

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

111001002100020 is a wasteful number, since it uses less digits than its factorization.

111001002100020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2990381 (or 2990376 counting only the distinct ones).

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

Adding to 111001002100020 its reverse (20001200100111), we get a palindrome (131002202200131).

The spelling of 111001002100020 in words is "one hundred eleven trillion, one billion, two million, one hundred thousand, twenty".