221481792 has 168 divisors, whose sum is σ = 732145856. Its totient is φ = 62705664.

The previous prime is 221481791. The next prime is 221481823. The reversal of 221481792 is 297184122.

It is a tau number, because it is divible by the number of its divisors (168).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221481791) 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, 657048 + ... + 657384.

Almost surely, 2^221481792 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 221481792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (366072928).

221481792 is an abundant number, since it is smaller than the sum of its proper divisors (510664064).

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

221481792 is a wasteful number, since it uses less digits than its factorization.

221481792 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 525 (or 512 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 221481792 is about 14882.2643438423. The cubic root of 221481792 is about 605.0333902296.

The spelling of 221481792 in words is "two hundred twenty-one million, four hundred eighty-one thousand, seven hundred ninety-two".