221011000128 has 84 divisors (see below), whose sum is σ = 635487037380. Its totient is φ = 73437874176.

The previous prime is 221011000127. The next prime is 221011000181. The reversal of 221011000128 is 821000110122.

It can be written as a sum of positive squares in 2 ways, for example, as 29019803904 + 191991196224 = 170352^2 + 438168^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a self number, because there is not a number n which added to its sum of digits gives 221011000128.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221011000121) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 422613 + ... + 787796.

Almost surely, 2^221011000128 is an apocalyptic number.

It is an amenable number.

221011000128 is an abundant number, since it is smaller than the sum of its proper divisors (414476037252).

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

221011000128 is a wasteful number, since it uses less digits than its factorization.

221011000128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1210744 (or 1210731 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

The spelling of 221011000128 in words is "two hundred twenty-one billion, eleven million, one hundred twenty-eight", and thus it is an aban number.