221405552 has 20 divisors (see below), whose sum is σ = 454207536. Its totient is φ = 104190720.

The previous prime is 221405549. The next prime is 221405557. The reversal of 221405552 is 255504122.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221405557) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 406724 + ... + 407267.

Almost surely, 2^221405552 is an apocalyptic number.

It is an amenable number.

221405552 is an abundant number, since it is smaller than the sum of its proper divisors (232801984).

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

221405552 is a wasteful number, since it uses less digits than its factorization.

221405552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 814016 (or 814010 counting only the distinct ones).

The product of its (nonzero) digits is 4000, while the sum is 26.

The square root of 221405552 is about 14879.7026852017. The cubic root of 221405552 is about 604.9639593311.

Adding to 221405552 its reverse (255504122), we get a palindrome (476909674).

The spelling of 221405552 in words is "two hundred twenty-one million, four hundred five thousand, five hundred fifty-two".