21020102021200 has 120 divisors (see below), whose sum is σ = 51467657162688. Its totient is φ = 8248590704640.

The previous prime is 21020102021183. The next prime is 21020102021251. The reversal of 21020102021200 is 212020102012.

It is a happy number.

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, 2024304 + ... + 6792496.

Almost surely, 2^{21020102021200} is an apocalyptic number.

21020102021200 is a gapful number since it is divisible by the number (20) 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 21020102021200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25733828581344).

21020102021200 is an abundant number, since it is smaller than the sum of its proper divisors (30447555141488).

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

21020102021200 is a wasteful number, since it uses less digits than its factorization.

21020102021200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4768421 (or 4768410 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21020102021200 its reverse (212020102012), we get a palindrome (21232122123212).

The spelling of 21020102021200 in words is "twenty-one trillion, twenty billion, one hundred two million, twenty-one thousand, two hundred".