221553420 has 72 divisors (see below), whose sum is σ = 681894192. Its totient is φ = 53708160.

The previous prime is 221553419. The next prime is 221553443. The reversal of 221553420 is 24355122.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7999 + ... + 22518.

Almost surely, 2^221553420 is an apocalyptic number.

221553420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221553420 is an abundant number, since it is smaller than the sum of its proper divisors (460340772).

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

221553420 is a wasteful number, since it uses less digits than its factorization.

221553420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30551 (or 30538 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 24.

The square root of 221553420 is about 14884.6706379416. The cubic root of 221553420 is about 605.0986065172.

The spelling of 221553420 in words is "two hundred twenty-one million, five hundred fifty-three thousand, four hundred twenty".