221223451 has 2 divisors, whose sum is σ = 221223452. Its totient is φ = 221223450.

The previous prime is 221223421. The next prime is 221223467. The reversal of 221223451 is 154322122.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221223451 - 2⁷ = 221223323 is a prime.

It is not a weakly prime, because it can be changed into another prime (221223421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110611725 + 110611726.

It is an arithmetic number, because the mean of its divisors is an integer number (110611726).

Almost surely, 2^221223451 is an apocalyptic number.

221223451 is a deficient number, since it is larger than the sum of its proper divisors (1).

221223451 is an equidigital number, since it uses as much as digits as its factorization.

221223451 is an evil number, because the sum of its binary digits is even.

The product of its digits is 960, while the sum is 22.

The square root of 221223451 is about 14873.5823189977. The cubic root of 221223451 is about 604.7980575017.

Adding to 221223451 its reverse (154322122), we get a palindrome (375545573).

The spelling of 221223451 in words is "two hundred twenty-one million, two hundred twenty-three thousand, four hundred fifty-one".