221425553 has 4 divisors (see below), whose sum is σ = 224730480. Its totient is φ = 218120628.

The previous prime is 221425549. The next prime is 221425627. The reversal of 221425553 is 355524122.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 221425553 - 2² = 221425549 is a prime.

It is a super-3 number, since 3×221425553³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221425453) 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, 1652363 + ... + 1652496.

It is an arithmetic number, because the mean of its divisors is an integer number (56182620).

Almost surely, 2^221425553 is an apocalyptic number.

It is an amenable number.

221425553 is a deficient number, since it is larger than the sum of its proper divisors (3304927).

221425553 is an equidigital number, since it uses as much as digits as its factorization.

221425553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3304926.

The product of its digits is 12000, while the sum is 29.

The square root of 221425553 is about 14880.3747600657. The cubic root of 221425553 is about 604.9821755557.

Adding to 221425553 its reverse (355524122), we get a palindrome (576949675).

The spelling of 221425553 in words is "two hundred twenty-one million, four hundred twenty-five thousand, five hundred fifty-three".