201221210021000 has 128 divisors (see below), whose sum is σ = 515390196353760. Its totient is φ = 73079077248000.

The previous prime is 201221210020933. The next prime is 201221210021081. The reversal of 201221210021000 is 120012122102.

201221210021000 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 16 ways, for example, as 25171673711044 + 176049536309956 = 5017138^2 + 13268366^2 .

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, 126080399 + ... + 127666398.

Almost surely, 2^{201221210021000} is an apocalyptic number.

201221210021000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201221210021000 is an abundant number, since it is smaller than the sum of its proper divisors (314168986332760).

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

201221210021000 is a wasteful number, since it uses less digits than its factorization.

201221210021000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253746892 (or 253746878 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 201221210021000 its reverse (120012122102), we get a palindrome (201341222143102).

The spelling of 201221210021000 in words is "two hundred one trillion, two hundred twenty-one billion, two hundred ten million, twenty-one thousand".