1278997 has 2 divisors, whose sum is σ = 1278998. Its totient is φ = 1278996.

The previous prime is 1278983. The next prime is 1279001. The reversal of 1278997 is 7998721.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1274641 + 4356 = 1129^2 + 66^2 .

It is a cyclic number.

It is not a de Polignac number, because 1278997 - 2¹¹ = 1276949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1278097) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 639498 + 639499.

It is an arithmetic number, because the mean of its divisors is an integer number (639499).

2^1278997 is an apocalyptic number.

It is an amenable number.

1278997 is a deficient number, since it is larger than the sum of its proper divisors (1).

1278997 is an equidigital number, since it uses as much as digits as its factorization.

1278997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 63504, while the sum is 43.

The square root of 1278997 is about 1130.9274954656. The cubic root of 1278997 is about 108.5483372439.

The spelling of 1278997 in words is "one million, two hundred seventy-eight thousand, nine hundred ninety-seven".