221553451 has 12 divisors (see below), whose sum is σ = 260140248. Its totient is φ = 188123712.

The previous prime is 221553443. The next prime is 221553473. The reversal of 221553451 is 154355122.

221553451 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221553451 - 2³ = 221553443 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221553481) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15886 + ... + 26371.

It is an arithmetic number, because the mean of its divisors is an integer number (21678354).

Almost surely, 2^221553451 is an apocalyptic number.

221553451 is a deficient number, since it is larger than the sum of its proper divisors (38586797).

221553451 is a wasteful number, since it uses less digits than its factorization.

221553451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42378 (or 42371 counting only the distinct ones).

The product of its digits is 6000, while the sum is 28.

The square root of 221553451 is about 14884.6716792813. The cubic root of 221553451 is about 605.0986347392.

The spelling of 221553451 in words is "two hundred twenty-one million, five hundred fifty-three thousand, four hundred fifty-one".