21012021210000 has 800 divisors, whose sum is σ = 69585407641728. Its totient is φ = 5460848640000.

The previous prime is 21012021209989. The next prime is 21012021210013. The reversal of 21012021210000 is 1212021012.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 87186809880 + ... + 87186810120.

Almost surely, 2^{21012021210000} is an apocalyptic number.

21012021210000 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 21012021210000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34792703820864).

21012021210000 is an abundant number, since it is smaller than the sum of its proper divisors (48573386431728).

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

21012021210000 is a wasteful number, since it uses less digits than its factorization.

21012021210000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 709 (or 688 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21012021210000 its reverse (1212021012), we get a palindrome (21013233231012).

The spelling of 21012021210000 in words is "twenty-one trillion, twelve billion, twenty-one million, two hundred ten thousand".