1340442421 has 2 divisors, whose sum is σ = 1340442422. Its totient is φ = 1340442420.

The previous prime is 1340442391. The next prime is 1340442427. The reversal of 1340442421 is 1242440431.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1320959025 + 19483396 = 36345^2 + 4414^2 .

It is a cyclic number.

It is not a de Polignac number, because 1340442421 - 2¹¹ = 1340440373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1340442427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 670221210 + 670221211.

It is an arithmetic number, because the mean of its divisors is an integer number (670221211).

Almost surely, 2^1340442421 is an apocalyptic number.

It is an amenable number.

1340442421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1340442421 is an equidigital number, since it uses as much as digits as its factorization.

1340442421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3072, while the sum is 25.

The square root of 1340442421 is about 36612.0529470829. The cubic root of 1340442421 is about 1102.5950908224.

Adding to 1340442421 its reverse (1242440431), we get a palindrome (2582882852).

The spelling of 1340442421 in words is "one billion, three hundred forty million, four hundred forty-two thousand, four hundred twenty-one".