1276238749 has 2 divisors, whose sum is σ = 1276238750. Its totient is φ = 1276238748.

The previous prime is 1276238741. The next prime is 1276238771. The reversal of 1276238749 is 9478326721.

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., 1037999524 + 238239225 = 32218^2 + 15435^2 .

It is a cyclic number.

It is not a de Polignac number, because 1276238749 - 2³ = 1276238741 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1276238741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 638119374 + 638119375.

It is an arithmetic number, because the mean of its divisors is an integer number (638119375).

Almost surely, 2^1276238749 is an apocalyptic number.

It is an amenable number.

1276238749 is a deficient number, since it is larger than the sum of its proper divisors (1).

1276238749 is an equidigital number, since it uses as much as digits as its factorization.

1276238749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1016064, while the sum is 49.

The square root of 1276238749 is about 35724.4838871047. The cubic root of 1276238749 is about 1084.7025026209.

The spelling of 1276238749 in words is "one billion, two hundred seventy-six million, two hundred thirty-eight thousand, seven hundred forty-nine".