1380657749 has 2 divisors, whose sum is σ = 1380657750. Its totient is φ = 1380657748.

The previous prime is 1380657727. The next prime is 1380657809. The reversal of 1380657749 is 9477560831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 884170225 + 496487524 = 29735^2 + 22282^2 .

It is an emirp because it is prime and its reverse (9477560831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1380657749 - 2¹² = 1380653653 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1380657697 and 1380657706.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1380657709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 690328874 + 690328875.

It is an arithmetic number, because the mean of its divisors is an integer number (690328875).

Almost surely, 2^1380657749 is an apocalyptic number.

It is an amenable number.

1380657749 is a deficient number, since it is larger than the sum of its proper divisors (1).

1380657749 is an equidigital number, since it uses as much as digits as its factorization.

1380657749 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1270080, while the sum is 50.

The square root of 1380657749 is about 37157.2031913060. The cubic root of 1380657749 is about 1113.5131364755.

The spelling of 1380657749 in words is "one billion, three hundred eighty million, six hundred fifty-seven thousand, seven hundred forty-nine".