21010020121000 has 64 divisors (see below), whose sum is σ = 49165287312960. Its totient is φ = 8403693480000.

The previous prime is 21010020120989. The next prime is 21010020121067. The reversal of 21010020121000 is 12102001012.

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

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27311635 + ... + 28070365.

It is an arithmetic number, because the mean of its divisors is an integer number (768207614265).

Almost surely, 2^{21010020121000} is an apocalyptic number.

21010020121000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21010020121000 is an abundant number, since it is smaller than the sum of its proper divisors (28155267191960).

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

21010020121000 is a wasteful number, since it uses less digits than its factorization.

21010020121000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 786443 (or 786429 counting only the distinct ones).

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

Adding to 21010020121000 its reverse (12102001012), we get a palindrome (21022122122012).

The spelling of 21010020121000 in words is "twenty-one trillion, ten billion, twenty million, one hundred twenty-one thousand".