1212000100020 has 576 divisors, whose sum is σ = 3965291366400. Its totient is φ = 299091087360.

The previous prime is 1212000100019. The next prime is 1212000100067. The reversal of 1212000100020 is 200010002121.

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 = 1212000099975 and 1212000100011.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 4505576446 + ... + 4505576714.

It is an arithmetic number, because the mean of its divisors is an integer number (6884186400).

Almost surely, 2^{1212000100020} is an apocalyptic number.

1212000100020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1212000100020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1982645683200).

1212000100020 is an abundant number, since it is smaller than the sum of its proper divisors (2753291266380).

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

1212000100020 is a wasteful number, since it uses less digits than its factorization.

1212000100020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 648 (or 643 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 1212000100020 its reverse (200010002121), we get a palindrome (1412010102141).

The spelling of 1212000100020 in words is "one trillion, two hundred twelve billion, one hundred thousand, twenty".