1221434423 has 4 divisors (see below), whose sum is σ = 1332473928. Its totient is φ = 1110394920.

The previous prime is 1221434413. The next prime is 1221434429. The reversal of 1221434423 is 3244341221.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1221434423 - 2⁶ = 1221434359 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221434392 and 1221434401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221434429) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55519736 + ... + 55519757.

It is an arithmetic number, because the mean of its divisors is an integer number (333118482).

Almost surely, 2^1221434423 is an apocalyptic number.

1221434423 is a deficient number, since it is larger than the sum of its proper divisors (111039505).

1221434423 is a wasteful number, since it uses less digits than its factorization.

1221434423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111039504.

The product of its digits is 4608, while the sum is 26.

The square root of 1221434423 is about 34949.0260665444. The cubic root of 1221434423 is about 1068.9483430751.

Adding to 1221434423 its reverse (3244341221), we get a palindrome (4465775644).

The spelling of 1221434423 in words is "one billion, two hundred twenty-one million, four hundred thirty-four thousand, four hundred twenty-three".