1210001200020 has 120 divisors (see below), whose sum is σ = 3796549833384. Its totient is φ = 322604826624.

The previous prime is 1210001199943. The next prime is 1210001200039. The reversal of 1210001200020 is 200021000121.

It can be written as a sum of positive squares in 4 ways, for example, as 94320237456 + 1115680962564 = 307116^2 + 1056258^2 .

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 = 1210001199975 and 1210001200011.

It is a congruent number.

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 39 ways as a sum of consecutive naturals, for example, 8667412 + ... + 8805908.

Almost surely, 2^{1210001200020} is an apocalyptic number.

1210001200020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1210001200020 is an abundant number, since it is smaller than the sum of its proper divisors (2586548633364).

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

1210001200020 is a wasteful number, since it uses less digits than its factorization.

1210001200020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143911 (or 143900 counting only the distinct ones).

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

Adding to 1210001200020 its reverse (200021000121), we get a palindrome (1410022200141).

The spelling of 1210001200020 in words is "one trillion, two hundred ten billion, one million, two hundred thousand, twenty".