221401232 has 40 divisors (see below), whose sum is σ = 468886656. Its totient is φ = 100653696.

The previous prime is 221401199. The next prime is 221401261. The reversal of 221401232 is 232104122.

It is a super-2 number, since 2×221401232² = 98037011062235648, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 221401232.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5993 + ... + 21879.

Almost surely, 2^221401232 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 221401232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (234443328).

221401232 is an abundant number, since it is smaller than the sum of its proper divisors (247485424).

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

221401232 is a wasteful number, since it uses less digits than its factorization.

221401232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15975 (or 15969 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 221401232 is about 14879.5575203028. The cubic root of 221401232 is about 604.9600246792.

Adding to 221401232 its reverse (232104122), we get a palindrome (453505354).

The spelling of 221401232 in words is "two hundred twenty-one million, four hundred one thousand, two hundred thirty-two".