221887202172 has 12 divisors (see below), whose sum is σ = 517736805096. Its totient is φ = 73962400720.

The previous prime is 221887202153. The next prime is 221887202179. The reversal of 221887202172 is 271202788122.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221887202179) 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 3 ways as a sum of consecutive naturals, for example, 9245300079 + ... + 9245300102.

It is an arithmetic number, because the mean of its divisors is an integer number (43144733758).

Almost surely, 2^221887202172 is an apocalyptic number.

It is an amenable number.

221887202172 is an abundant number, since it is smaller than the sum of its proper divisors (295849602924).

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

221887202172 is a wasteful number, since it uses less digits than its factorization.

221887202172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18490600188 (or 18490600186 counting only the distinct ones).

The product of its (nonzero) digits is 100352, while the sum is 42.

The spelling of 221887202172 in words is "two hundred twenty-one billion, eight hundred eighty-seven million, two hundred two thousand, one hundred seventy-two".