221855185020 has 48 divisors (see below), whose sum is σ = 709936593408. Its totient is φ = 50709756480.

The previous prime is 221855185009. The next prime is 221855185049. The reversal of 221855185020 is 20581558122.

It is a self number, because there is not a number n which added to its sum of digits gives 221855185020.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 264112896 + ... + 264113735.

It is an arithmetic number, because the mean of its divisors is an integer number (14790345696).

Almost surely, 2^221855185020 is an apocalyptic number.

221855185020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221855185020 is an abundant number, since it is smaller than the sum of its proper divisors (488081408388).

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

221855185020 is a wasteful number, since it uses less digits than its factorization.

221855185020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 528226650 (or 528226648 counting only the distinct ones).

The product of its (nonzero) digits is 64000, while the sum is 39.

The spelling of 221855185020 in words is "two hundred twenty-one billion, eight hundred fifty-five million, one hundred eighty-five thousand, twenty".