221525512 has 64 divisors (see below), whose sum is σ = 479566080. Its totient is φ = 95116032.

The previous prime is 221525509. The next prime is 221525533. The reversal of 221525512 is 215525122.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 87253 + ... + 89755.

It is an arithmetic number, because the mean of its divisors is an integer number (7493220).

Almost surely, 2^221525512 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 221525512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (239783040).

221525512 is an abundant number, since it is smaller than the sum of its proper divisors (258040568).

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

221525512 is a wasteful number, since it uses less digits than its factorization.

221525512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2582 (or 2578 counting only the distinct ones).

The product of its digits is 2000, while the sum is 25.

The square root of 221525512 is about 14883.7331338613. The cubic root of 221525512 is about 605.0731983470.

The spelling of 221525512 in words is "two hundred twenty-one million, five hundred twenty-five thousand, five hundred twelve".