1340212421 has 2 divisors, whose sum is σ = 1340212422. Its totient is φ = 1340212420.

The previous prime is 1340212417. The next prime is 1340212441. The reversal of 1340212421 is 1242120431.

It is an a-pointer prime, because the next prime (1340212441) can be obtained adding 1340212421 to its sum of digits (20).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1338535396 + 1677025 = 36586^2 + 1295^2 .

It is a cyclic number.

It is not a de Polignac number, because 1340212421 - 2² = 1340212417 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1340212393 and 1340212402.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1340212411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 670106210 + 670106211.

It is an arithmetic number, because the mean of its divisors is an integer number (670106211).

Almost surely, 2^1340212421 is an apocalyptic number.

It is an amenable number.

1340212421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1340212421 is an equidigital number, since it uses as much as digits as its factorization.

1340212421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 1340212421 is about 36608.9117702234. The cubic root of 1340212421 is about 1102.5320242376.

Adding to 1340212421 its reverse (1242120431), we get a palindrome (2582332852).

The spelling of 1340212421 in words is "one billion, three hundred forty million, two hundred twelve thousand, four hundred twenty-one".