21201000212220 has 24 divisors (see below), whose sum is σ = 59362800594384. Its totient is φ = 5653600056576.

The previous prime is 21201000212179. The next prime is 21201000212281. The reversal of 21201000212220 is 2221200010212.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21201000212220.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 176675001709 + ... + 176675001828.

It is an arithmetic number, because the mean of its divisors is an integer number (2473450024766).

Almost surely, 2^{21201000212220} is an apocalyptic number.

21201000212220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201000212220 is an abundant number, since it is smaller than the sum of its proper divisors (38161800382164).

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

21201000212220 is a wasteful number, since it uses less digits than its factorization.

21201000212220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 353350003549 (or 353350003547 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21201000212220 its reverse (2221200010212), we get a palindrome (23422200222432).

The spelling of 21201000212220 in words is "twenty-one trillion, two hundred one billion, two hundred twelve thousand, two hundred twenty".