221323401 has 64 divisors (see below), whose sum is σ = 365783040. Its totient is φ = 131423040.

The previous prime is 221323379. The next prime is 221323409. The reversal of 221323401 is 104323122.

It is not a de Polignac number, because 221323401 - 2⁵ = 221323369 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221323409) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2068390 + ... + 2068496.

It is an arithmetic number, because the mean of its divisors is an integer number (5715360).

Almost surely, 2^221323401 is an apocalyptic number.

It is an amenable number.

221323401 is a deficient number, since it is larger than the sum of its proper divisors (144459639).

221323401 is a wasteful number, since it uses less digits than its factorization.

221323401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 283 (or 277 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 221323401 is about 14876.9419236616. The cubic root of 221323401 is about 604.8891275096.

Adding to 221323401 its reverse (104323122), we get a palindrome (325646523).

The spelling of 221323401 in words is "two hundred twenty-one million, three hundred twenty-three thousand, four hundred one".