1387291 has 4 divisors (see below), whose sum is σ = 1447632. Its totient is φ = 1326952.

The previous prime is 1387289. The next prime is 1387313. The reversal of 1387291 is 1927831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1927831 = 181 ⋅10651.

It is a cyclic number.

It is not a de Polignac number, because 1387291 - 2¹ = 1387289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1387231) 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, 30136 + ... + 30181.

It is an arithmetic number, because the mean of its divisors is an integer number (361908).

2^1387291 is an apocalyptic number.

1387291 is a deficient number, since it is larger than the sum of its proper divisors (60341).

1387291 is an equidigital number, since it uses as much as digits as its factorization.

1387291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60340.

The product of its digits is 3024, while the sum is 31.

The square root of 1387291 is about 1177.8331800387. The cubic root of 1387291 is about 111.5293547490.

The spelling of 1387291 in words is "one million, three hundred eighty-seven thousand, two hundred ninety-one".