1278634601 has 2 divisors, whose sum is σ = 1278634602. Its totient is φ = 1278634600.

The previous prime is 1278634579. The next prime is 1278634619. The reversal of 1278634601 is 1064368721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 950118976 + 328515625 = 30824^2 + 18125^2 .

It is a cyclic number.

It is not a de Polignac number, because 1278634601 - 2¹⁴ = 1278618217 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1278634661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 639317300 + 639317301.

It is an arithmetic number, because the mean of its divisors is an integer number (639317301).

Almost surely, 2^1278634601 is an apocalyptic number.

It is an amenable number.

1278634601 is a deficient number, since it is larger than the sum of its proper divisors (1).

1278634601 is an equidigital number, since it uses as much as digits as its factorization.

1278634601 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48384, while the sum is 38.

The square root of 1278634601 is about 35758.0005173667. Note that the first 3 decimals coincide. The cubic root of 1278634601 is about 1085.3808402081.

The spelling of 1278634601 in words is "one billion, two hundred seventy-eight million, six hundred thirty-four thousand, six hundred one".