221957892 has 72 divisors (see below), whose sum is σ = 623750400. Its totient is φ = 66087360.

The previous prime is 221957891. The next prime is 221957927. The reversal of 221957892 is 298759122.

It is a happy number.

221957892 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (221957891) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6859 + ... + 22157.

It is an arithmetic number, because the mean of its divisors is an integer number (8663200).

Almost surely, 2^221957892 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 221957892, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (311875200).

221957892 is an abundant number, since it is smaller than the sum of its proper divisors (401792508).

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

221957892 is a wasteful number, since it uses less digits than its factorization.

221957892 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15353 (or 15348 counting only the distinct ones).

The product of its digits is 181440, while the sum is 45.

The square root of 221957892 is about 14898.2513067809. The cubic root of 221957892 is about 605.4666090471.

The spelling of 221957892 in words is "two hundred twenty-one million, nine hundred fifty-seven thousand, eight hundred ninety-two".