221121992 has 96 divisors (see below), whose sum is σ = 542579520. Its totient is φ = 82252800.

The previous prime is 221121919. The next prime is 221121997. The reversal of 221121992 is 299121122.

It is not an unprimeable number, because it can be changed into a prime (221121997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 209867 + ... + 210917.

It is an arithmetic number, because the mean of its divisors is an integer number (5651870).

Almost surely, 2^221121992 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221121992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (271289760).

221121992 is an abundant number, since it is smaller than the sum of its proper divisors (321457528).

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

221121992 is a wasteful number, since it uses less digits than its factorization.

221121992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1111 (or 1090 counting only the distinct ones).

The product of its digits is 1296, while the sum is 29.

The square root of 221121992 is about 14870.1712162302. The cubic root of 221121992 is about 604.7055845005.

The spelling of 221121992 in words is "two hundred twenty-one million, one hundred twenty-one thousand, nine hundred ninety-two".