21211201002120 has 64 divisors (see below), whose sum is σ = 65353430128320. Its totient is φ = 5503446745344.

The previous prime is 21211201002091. The next prime is 21211201002127. The reversal of 21211201002120 is 2120010211212.

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 21211201002120.

It is not an unprimeable number, because it can be changed into a prime (21211201002127) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2388644322 + ... + 2388653201.

It is an arithmetic number, because the mean of its divisors is an integer number (1021147345755).

Almost surely, 2^{21211201002120} is an apocalyptic number.

21211201002120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21211201002120 is an abundant number, since it is smaller than the sum of its proper divisors (44142229126200).

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

21211201002120 is a wasteful number, since it uses less digits than its factorization.

21211201002120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4777297574 (or 4777297570 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21211201002120 its reverse (2120010211212), we get a palindrome (23331211213332).

The spelling of 21211201002120 in words is "twenty-one trillion, two hundred eleven billion, two hundred one million, two thousand, one hundred twenty".