1001200021200 has 90 divisors (see below), whose sum is σ = 3474442197174. Its totient is φ = 266986671360.

The previous prime is 1001200021193. The next prime is 1001200021229. The reversal of 1001200021200 is 21200021001.

It can be written as a sum of positive squares in 3 ways, for example, as 41215496256 + 959984524944 = 203016^2 + 979788^2 .

It is a tau number, because it is divible by the number of its divisors (90).

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 139051959 + ... + 139059158.

Almost surely, 2^{1001200021200} is an apocalyptic number.

1001200021200 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1001200021200 is an abundant number, since it is smaller than the sum of its proper divisors (2473242175974).

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

1001200021200 is a wasteful number, since it uses less digits than its factorization.

1001200021200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278111141 (or 278111127 counting only the distinct ones).

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

Adding to 1001200021200 its reverse (21200021001), we get a palindrome (1022400042201).

The spelling of 1001200021200 in words is "one trillion, one billion, two hundred million, twenty-one thousand, two hundred".