21001201210220 has 96 divisors (see below), whose sum is σ = 55017914757120. Its totient is φ = 6541906141440.

The previous prime is 21001201210219. The next prime is 21001201210247. The reversal of 21001201210220 is 2201210210012.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 21001201210195 and 21001201210204.

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, 1515164 + ... + 6655683.

It is an arithmetic number, because the mean of its divisors is an integer number (573103278720).

Almost surely, 2^{21001201210220} is an apocalyptic number.

21001201210220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21001201210220 is an abundant number, since it is smaller than the sum of its proper divisors (34016713546900).

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

21001201210220 is a wasteful number, since it uses less digits than its factorization.

21001201210220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8172543 (or 8172541 counting only the distinct ones).

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

Adding to 21001201210220 its reverse (2201210210012), we get a palindrome (23202411420232).

The spelling of 21001201210220 in words is "twenty-one trillion, one billion, two hundred one million, two hundred ten thousand, two hundred twenty".