211221010020 has 48 divisors (see below), whose sum is σ = 593957145600. Its totient is φ = 56083858176.

The previous prime is 211221010003. The next prime is 211221010109. The reversal of 211221010020 is 20010122112.

It is a super-2 number, since 2×211221010020² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 211221009978 and 211221010005.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7540420 + ... + 7568379.

It is an arithmetic number, because the mean of its divisors is an integer number (12374107200).

Almost surely, 2^211221010020 is an apocalyptic number.

211221010020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

211221010020 is an abundant number, since it is smaller than the sum of its proper divisors (382736135580).

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

211221010020 is a wasteful number, since it uses less digits than its factorization.

211221010020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15109044 (or 15109042 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 211221010020 its reverse (20010122112), we get a palindrome (231231132132).

The spelling of 211221010020 in words is "two hundred eleven billion, two hundred twenty-one million, ten thousand, twenty".