1340224021 has 2 divisors, whose sum is σ = 1340224022. Its totient is φ = 1340224020.

The previous prime is 1340224013. The next prime is 1340224049. The reversal of 1340224021 is 1204220431.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1093294225 + 246929796 = 33065^2 + 15714^2 .

It is an emirp because it is prime and its reverse (1204220431) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1340224021 - 2³ = 1340224013 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1340224021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1340224051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 670112010 + 670112011.

It is an arithmetic number, because the mean of its divisors is an integer number (670112011).

Almost surely, 2^1340224021 is an apocalyptic number.

It is an amenable number.

1340224021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1340224021 is an equidigital number, since it uses as much as digits as its factorization.

1340224021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 1340224021 is about 36609.0702012493. The cubic root of 1340224021 is about 1102.5352051599.

Adding to 1340224021 its reverse (1204220431), we get a palindrome (2544444452).

The spelling of 1340224021 in words is "one billion, three hundred forty million, two hundred twenty-four thousand, twenty-one".