21012001001200 has 120 divisors (see below), whose sum is σ = 55072349603856. Its totient is φ = 7640477184000.

The previous prime is 21012001001191. The next prime is 21012001001209. The reversal of 21012001001200 is 210010021012.

It is an interprime number because it is at equal distance from previous prime (21012001001191) and next prime (21012001001209).

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012001001209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 182634894 + ... + 182749906.

Almost surely, 2^{21012001001200} is an apocalyptic number.

21012001001200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21012001001200 is an abundant number, since it is smaller than the sum of its proper divisors (34060348602656).

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

21012001001200 is a wasteful number, since it uses less digits than its factorization.

21012001001200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156563 (or 156552 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21012001001200 its reverse (210010021012), we get a palindrome (21222011022212).

The spelling of 21012001001200 in words is "twenty-one trillion, twelve billion, one million, one thousand, two hundred".