221332451 has 2 divisors, whose sum is σ = 221332452. Its totient is φ = 221332450.

The previous prime is 221332439. The next prime is 221332453. The reversal of 221332451 is 154233122.

221332451 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221332451 - 2¹⁰ = 221331427 is a prime.

Together with 221332453, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (221332453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110666225 + 110666226.

It is an arithmetic number, because the mean of its divisors is an integer number (110666226).

Almost surely, 2^221332451 is an apocalyptic number.

221332451 is a deficient number, since it is larger than the sum of its proper divisors (1).

221332451 is an equidigital number, since it uses as much as digits as its factorization.

221332451 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1440, while the sum is 23.

The square root of 221332451 is about 14877.2460825248. The cubic root of 221332451 is about 604.8973721145.

Adding to 221332451 its reverse (154233122), we get a palindrome (375565573).

The spelling of 221332451 in words is "two hundred twenty-one million, three hundred thirty-two thousand, four hundred fifty-one".