221642452 has 6 divisors (see below), whose sum is σ = 387874298. Its totient is φ = 110821224.

The previous prime is 221642431. The next prime is 221642471. The reversal of 221642452 is 254246122.

It can be written as a sum of positive squares in only one way, i.e., 198640836 + 23001616 = 14094^2 + 4796^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 221642452.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27705303 + ... + 27705310.

Almost surely, 2^221642452 is an apocalyptic number.

It is an amenable number.

221642452 is a deficient number, since it is larger than the sum of its proper divisors (166231846).

221642452 is a wasteful number, since it uses less digits than its factorization.

221642452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55410617 (or 55410615 counting only the distinct ones).

The product of its digits is 7680, while the sum is 28.

The square root of 221642452 is about 14887.6610654595. The cubic root of 221642452 is about 605.1796493109.

Adding to 221642452 its reverse (254246122), we get a palindrome (475888574).

The spelling of 221642452 in words is "two hundred twenty-one million, six hundred forty-two thousand, four hundred fifty-two".