221012000100 has 216 divisors, whose sum is σ = 719476528680. Its totient is φ = 56698583040.

The previous prime is 221012000059. The next prime is 221012000141. The reversal of 221012000100 is 1000210122.

It is an interprime number because it is at equal distance from previous prime (221012000059) and next prime (221012000141).

It can be written as a sum of positive squares in 12 ways, for example, as 28320850944 + 192691149156 = 168288^2 + 438966^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 2926414 + ... + 3000986.

It is an arithmetic number, because the mean of its divisors is an integer number (3330909855).

Almost surely, 2^221012000100 is an apocalyptic number.

221012000100 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 221012000100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (359738264340).

221012000100 is an abundant number, since it is smaller than the sum of its proper divisors (498464528580).

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

221012000100 is a wasteful number, since it uses less digits than its factorization.

221012000100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74719 (or 74709 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 221012000100 its reverse (1000210122), we get a palindrome (222012210222).

The spelling of 221012000100 in words is "two hundred twenty-one billion, twelve million, one hundred", and thus it is an aban number.