221553473 has 2 divisors, whose sum is σ = 221553474. Its totient is φ = 221553472.

The previous prime is 221553443. The next prime is 221553481. The reversal of 221553473 is 374355122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 204718864 + 16834609 = 14308^2 + 4103^2 .

It is a cyclic number.

It is not a de Polignac number, because 221553473 - 2²⁰ = 220504897 is a prime.

It is not a weakly prime, because it can be changed into another prime (221553443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110776736 + 110776737.

It is an arithmetic number, because the mean of its divisors is an integer number (110776737).

Almost surely, 2^221553473 is an apocalyptic number.

It is an amenable number.

221553473 is a deficient number, since it is larger than the sum of its proper divisors (1).

221553473 is an equidigital number, since it uses as much as digits as its factorization.

221553473 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25200, while the sum is 32.

The square root of 221553473 is about 14884.6724182966. The cubic root of 221553473 is about 605.0986547677.

The spelling of 221553473 in words is "two hundred twenty-one million, five hundred fifty-three thousand, four hundred seventy-three".