1243342421 has 4 divisors (see below), whose sum is σ = 1255652844. Its totient is φ = 1231032000.

The previous prime is 1243342403. The next prime is 1243342427. The reversal of 1243342421 is 1242433421.

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

It can be written as a sum of positive squares in 2 ways, for example, as 580279921 + 663062500 = 24089^2 + 25750^2 .

It is a cyclic number.

It is not a de Polignac number, because 1243342421 - 2⁶ = 1243342357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243342427) 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, 6155060 + ... + 6155261.

It is an arithmetic number, because the mean of its divisors is an integer number (313913211).

Almost surely, 2^1243342421 is an apocalyptic number.

It is an amenable number.

1243342421 is a deficient number, since it is larger than the sum of its proper divisors (12310423).

1243342421 is a wasteful number, since it uses less digits than its factorization.

1243342421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12310422.

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

The square root of 1243342421 is about 35261.0609738278. The cubic root of 1243342421 is about 1075.3014971173.

Adding to 1243342421 its reverse (1242433421), we get a palindrome (2485775842).

The spelling of 1243342421 in words is "one billion, two hundred forty-three million, three hundred forty-two thousand, four hundred twenty-one".