243642403 has 2 divisors, whose sum is σ = 243642404. Its totient is φ = 243642402.

The previous prime is 243642389. The next prime is 243642409. The reversal of 243642403 is 304246342.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243642403 is a prime.

It is a super-2 number, since 2×243642403² = 118723241079228818, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (243642409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121821201 + 121821202.

It is an arithmetic number, because the mean of its divisors is an integer number (121821202).

Almost surely, 2^243642403 is an apocalyptic number.

243642403 is a deficient number, since it is larger than the sum of its proper divisors (1).

243642403 is an equidigital number, since it uses as much as digits as its factorization.

243642403 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13824, while the sum is 28.

The square root of 243642403 is about 15609.0487538479. The cubic root of 243642403 is about 624.5745610284.

Adding to 243642403 its reverse (304246342), we get a palindrome (547888745).

The spelling of 243642403 in words is "two hundred forty-three million, six hundred forty-two thousand, four hundred three".