20021213121000 has 2048 divisors, whose sum is σ = 84904862515200. Its totient is φ = 3807195955200.

The previous prime is 20021213120959. The next prime is 20021213121043. The reversal of 20021213121000 is 12131212002.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 511 ways as a sum of consecutive naturals, for example, 30660356674 + ... + 30660357326.

It is an arithmetic number, because the mean of its divisors is an integer number (41457452400).

Almost surely, 2^{20021213121000} is an apocalyptic number.

20021213121000 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 20021213121000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42452431257600).

20021213121000 is an abundant number, since it is smaller than the sum of its proper divisors (64883649394200).

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

20021213121000 is a wasteful number, since it uses less digits than its factorization.

20021213121000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 996 (or 982 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 20021213121000 its reverse (12131212002), we get a palindrome (20033344333002).

The spelling of 20021213121000 in words is "twenty trillion, twenty-one billion, two hundred thirteen million, one hundred twenty-one thousand".