221772672 has 288 divisors, whose sum is σ = 737176440. Its totient is φ = 63866880.

The previous prime is 221772659. The next prime is 221772673. The reversal of 221772672 is 276277122.

It is a tau number, because it is divible by the number of its divisors (288).

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

Its product of digits (32928) is a multiple of the sum of its prime divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221772673) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 5157483 + ... + 5157525.

Almost surely, 2^221772672 is an apocalyptic number.

221772672 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221772672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (368588220).

221772672 is an abundant number, since it is smaller than the sum of its proper divisors (515403768).

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

221772672 is a wasteful number, since it uses less digits than its factorization.

221772672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122 (or 96 counting only the distinct ones).

The product of its digits is 32928, while the sum is 36.

The square root of 221772672 is about 14892.0338436360. The cubic root of 221772672 is about 605.2981450605.

The spelling of 221772672 in words is "two hundred twenty-one million, seven hundred seventy-two thousand, six hundred seventy-two".