1247663797 has 2 divisors, whose sum is σ = 1247663798. Its totient is φ = 1247663796.

The previous prime is 1247663783. The next prime is 1247663863. The reversal of 1247663797 is 7973667421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 673869681 + 573794116 = 25959^2 + 23954^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1247663797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1247663707) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 623831898 + 623831899.

It is an arithmetic number, because the mean of its divisors is an integer number (623831899).

Almost surely, 2^1247663797 is an apocalyptic number.

It is an amenable number.

1247663797 is a deficient number, since it is larger than the sum of its proper divisors (1).

1247663797 is an equidigital number, since it uses as much as digits as its factorization.

1247663797 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2667168, while the sum is 52.

The square root of 1247663797 is about 35322.2847080989. The cubic root of 1247663797 is about 1076.5458335940.

The spelling of 1247663797 in words is "one billion, two hundred forty-seven million, six hundred sixty-three thousand, seven hundred ninety-seven".