1378591 has 2 divisors, whose sum is σ = 1378592. Its totient is φ = 1378590.

The previous prime is 1378589. The next prime is 1378603. The reversal of 1378591 is 1958731.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (1958731) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1378591 - 2¹ = 1378589 is a prime.

Together with 1378589, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1378501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 689295 + 689296.

It is an arithmetic number, because the mean of its divisors is an integer number (689296).

2^1378591 is an apocalyptic number.

1378591 is a deficient number, since it is larger than the sum of its proper divisors (1).

1378591 is an equidigital number, since it uses as much as digits as its factorization.

1378591 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7560, while the sum is 34.

The square root of 1378591 is about 1174.1341490647. The cubic root of 1378591 is about 111.2957241664.

The spelling of 1378591 in words is "one million, three hundred seventy-eight thousand, five hundred ninety-one".