221531952 has 80 divisors (see below), whose sum is σ = 616531968. Its totient is φ = 68344320.

The previous prime is 221531951. The next prime is 221531953. The reversal of 221531952 is 259135122.

It is an interprime number because it is at equal distance from previous prime (221531951) and next prime (221531953).

It is not an unprimeable number, because it can be changed into a prime (221531951) 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, 30988 + ... + 37460.

Almost surely, 2^221531952 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 221531952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (308265984).

221531952 is an abundant number, since it is smaller than the sum of its proper divisors (395000016).

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

221531952 is a wasteful number, since it uses less digits than its factorization.

221531952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6538 (or 6532 counting only the distinct ones).

The product of its digits is 5400, while the sum is 30.

The square root of 221531952 is about 14883.9494758616. The cubic root of 221531952 is about 605.0790616801.

The spelling of 221531952 in words is "two hundred twenty-one million, five hundred thirty-one thousand, nine hundred fifty-two".