1278131 has 2 divisors, whose sum is σ = 1278132. Its totient is φ = 1278130.

The previous prime is 1278113. The next prime is 1278139. The reversal of 1278131 is 1318721.

It is a happy number.

Together with previous prime (1278113) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is an emirp because it is prime and its reverse (1318721) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1278131 - 2¹⁴ = 1261747 is a prime.

It is a super-2 number, since 2×1278131² = 3267237706322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1278097 and 1278106.

It is not a weakly prime, because it can be changed into another prime (1278139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 639065 + 639066.

It is an arithmetic number, because the mean of its divisors is an integer number (639066).

2^1278131 is an apocalyptic number.

1278131 is a deficient number, since it is larger than the sum of its proper divisors (1).

1278131 is an equidigital number, since it uses as much as digits as its factorization.

1278131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 336, while the sum is 23.

The square root of 1278131 is about 1130.5445590511. The cubic root of 1278131 is about 108.5238326036.

The spelling of 1278131 in words is "one million, two hundred seventy-eight thousand, one hundred thirty-one".