21001200022000 has 160 divisors (see below), whose sum is σ = 55401389244864. Its totient is φ = 7636242816000.

The previous prime is 21001200021979. The next prime is 21001200022057. The reversal of 21001200022000 is 22000210012.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 412628554 + ... + 412679446.

Almost surely, 2^{21001200022000} is an apocalyptic number.

21001200022000 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 21001200022000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27700694622432).

21001200022000 is an abundant number, since it is smaller than the sum of its proper divisors (34400189222864).

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

21001200022000 is a wasteful number, since it uses less digits than its factorization.

21001200022000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69684 (or 69668 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 21001200022000 its reverse (22000210012), we get a palindrome (21023200232012).

The spelling of 21001200022000 in words is "twenty-one trillion, one billion, two hundred million, twenty-two thousand".