1278753997 has 2 divisors, whose sum is σ = 1278753998. Its totient is φ = 1278753996.

The previous prime is 1278753911. The next prime is 1278754019. The reversal of 1278753997 is 7993578721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1021825156 + 256928841 = 31966^2 + 16029^2 .

It is a cyclic number.

It is not a de Polignac number, because 1278753997 - 2¹¹ = 1278751949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1278753397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 639376998 + 639376999.

It is an arithmetic number, because the mean of its divisors is an integer number (639376999).

Almost surely, 2^1278753997 is an apocalyptic number.

It is an amenable number.

1278753997 is a deficient number, since it is larger than the sum of its proper divisors (1).

1278753997 is an equidigital number, since it uses as much as digits as its factorization.

1278753997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6667920, while the sum is 58.

The square root of 1278753997 is about 35759.6699789022. The cubic root of 1278753997 is about 1085.4146226239.

The spelling of 1278753997 in words is "one billion, two hundred seventy-eight million, seven hundred fifty-three thousand, nine hundred ninety-seven".