221571072 has 96 divisors (see below), whose sum is σ = 656510400. Its totient is φ = 73838592.

The previous prime is 221571067. The next prime is 221571079. The reversal of 221571072 is 270175122.

221571072 is a `hidden beast` number, since 2 + 21 + 571 + 0 + 72 = 666.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (221571079) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53293 + ... + 57299.

It is an arithmetic number, because the mean of its divisors is an integer number (6838650).

Almost surely, 2^221571072 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 221571072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (328255200).

221571072 is an abundant number, since it is smaller than the sum of its proper divisors (434939328).

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

221571072 is an equidigital number, since it uses as much as digits as its factorization.

221571072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4038 (or 4012 counting only the distinct ones).

The product of its (nonzero) digits is 1960, while the sum is 27.

The square root of 221571072 is about 14885.2635851704. The cubic root of 221571072 is about 605.1146762562.

The spelling of 221571072 in words is "two hundred twenty-one million, five hundred seventy-one thousand, seventy-two".