1340240357 has 2 divisors, whose sum is σ = 1340240358. Its totient is φ = 1340240356.

The previous prime is 1340240303. The next prime is 1340240359. The reversal of 1340240357 is 7530420431.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 931836676 + 408403681 = 30526^2 + 20209^2 .

It is a cyclic number.

It is not a de Polignac number, because 1340240357 - 2¹⁰ = 1340239333 is a prime.

Together with 1340240359, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1340240359) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 670120178 + 670120179.

It is an arithmetic number, because the mean of its divisors is an integer number (670120179).

Almost surely, 2^1340240357 is an apocalyptic number.

It is an amenable number.

1340240357 is a deficient number, since it is larger than the sum of its proper divisors (1).

1340240357 is an equidigital number, since it uses as much as digits as its factorization.

1340240357 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 29.

The square root of 1340240357 is about 36609.2933146763. The cubic root of 1340240357 is about 1102.5396847448.

Adding to 1340240357 its reverse (7530420431), we get a palindrome (8870660788).

The spelling of 1340240357 in words is "one billion, three hundred forty million, two hundred forty thousand, three hundred fifty-seven".