243220401 has 12 divisors (see below), whose sum is σ = 364330512. Its totient is φ = 162146772.

The previous prime is 243220391. The next prime is 243220421. The reversal of 243220401 is 104022342.

243220401 is a `hidden beast` number, since 2 + 43 + 220 + 401 = 666.

It is not a de Polignac number, because 243220401 - 2¹³ = 243212209 is a prime.

It is not an unprimeable number, because it can be changed into a prime (243220421) 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, 500211 + ... + 500696.

It is an arithmetic number, because the mean of its divisors is an integer number (30360876).

Almost surely, 2^243220401 is an apocalyptic number.

It is an amenable number.

243220401 is a deficient number, since it is larger than the sum of its proper divisors (121110111).

243220401 is an equidigital number, since it uses as much as digits as its factorization.

243220401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1000922 (or 1000910 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 243220401 is about 15595.5250312389. The cubic root of 243220401 is about 624.2137535078.

Adding to 243220401 its reverse (104022342), we get a palindrome (347242743).

The spelling of 243220401 in words is "two hundred forty-three million, two hundred twenty thousand, four hundred one".