1390843549 has 2 divisors, whose sum is σ = 1390843550. Its totient is φ = 1390843548.

The previous prime is 1390843547. The next prime is 1390843561. The reversal of 1390843549 is 9453480931.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1387041049 + 3802500 = 37243^2 + 1950^2 .

It is an emirp because it is prime and its reverse (9453480931) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1390843549 - 2¹ = 1390843547 is a prime.

Together with 1390843547, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1390843499 and 1390843508.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1390843547) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 695421774 + 695421775.

It is an arithmetic number, because the mean of its divisors is an integer number (695421775).

Almost surely, 2^1390843549 is an apocalyptic number.

It is an amenable number.

1390843549 is a deficient number, since it is larger than the sum of its proper divisors (1).

1390843549 is an equidigital number, since it uses as much as digits as its factorization.

1390843549 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 466560, while the sum is 46.

The square root of 1390843549 is about 37294.0149219684. The cubic root of 1390843549 is about 1116.2447436767.

The spelling of 1390843549 in words is "one billion, three hundred ninety million, eight hundred forty-three thousand, five hundred forty-nine".