221271972 has 48 divisors (see below), whose sum is σ = 537062400. Its totient is φ = 70819840.

The previous prime is 221271961. The next prime is 221271977. The reversal of 221271972 is 279172122.

It is a super-2 number, since 2×221271972² = 97922571185537568, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (221271977) 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 15 ways as a sum of consecutive naturals, for example, 64804 + ... + 68132.

It is an arithmetic number, because the mean of its divisors is an integer number (11188800).

Almost surely, 2^221271972 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 221271972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (268531200).

221271972 is an abundant number, since it is smaller than the sum of its proper divisors (315790428).

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

221271972 is a wasteful number, since it uses less digits than its factorization.

221271972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3556 (or 3554 counting only the distinct ones).

The product of its digits is 7056, while the sum is 33.

The square root of 221271972 is about 14875.2133430079. The cubic root of 221271972 is about 604.8422711105.

The spelling of 221271972 in words is "two hundred twenty-one million, two hundred seventy-one thousand, nine hundred seventy-two".