1291427 has 4 divisors (see below), whose sum is σ = 1347600. Its totient is φ = 1235256.

The previous prime is 1291421. The next prime is 1291447. The reversal of 1291427 is 7241921.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1291427 - 2¹⁶ = 1225891 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1291396 and 1291405.

It is not an unprimeable number, because it can be changed into a prime (1291421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28052 + ... + 28097.

It is an arithmetic number, because the mean of its divisors is an integer number (336900).

2^1291427 is an apocalyptic number.

1291427 is a deficient number, since it is larger than the sum of its proper divisors (56173).

1291427 is an equidigital number, since it uses as much as digits as its factorization.

1291427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56172.

The product of its digits is 1008, while the sum is 26.

The square root of 1291427 is about 1136.4096972483. The cubic root of 1291427 is about 108.8988484496.

The spelling of 1291427 in words is "one million, two hundred ninety-one thousand, four hundred twenty-seven".