221012100020 has 96 divisors (see below), whose sum is σ = 492234478848. Its totient is φ = 83180224512.

The previous prime is 221012099989. The next prime is 221012100031. The reversal of 221012100020 is 20001210122.

It is a happy number.

221012100020 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 221012099974 and 221012100010.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23326004 + ... + 23335476.

It is an arithmetic number, because the mean of its divisors is an integer number (5127442488).

Almost surely, 2^221012100020 is an apocalyptic number.

221012100020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221012100020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (246117239424).

221012100020 is an abundant number, since it is smaller than the sum of its proper divisors (271222378828).

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

221012100020 is a wasteful number, since it uses less digits than its factorization.

221012100020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10329 (or 10327 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 221012100020 its reverse (20001210122), we get a palindrome (241013310142).

The spelling of 221012100020 in words is "two hundred twenty-one billion, twelve million, one hundred thousand, twenty".