1397581 has 2 divisors, whose sum is σ = 1397582. Its totient is φ = 1397580.

The previous prime is 1397579. The next prime is 1397603. The reversal of 1397581 is 1857931.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1359556 + 38025 = 1166^2 + 195^2 .

It is an emirp because it is prime and its reverse (1857931) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1397581 - 2¹ = 1397579 is a prime.

It is a super-2 number, since 2×1397581² = 3906465303122, which contains 22 as substring.

Together with 1397579, it forms a pair of twin primes.

1397581 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1397521) 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 as a sum of consecutive naturals, namely, 698790 + 698791.

It is an arithmetic number, because the mean of its divisors is an integer number (698791).

2^1397581 is an apocalyptic number.

It is an amenable number.

1397581 is a deficient number, since it is larger than the sum of its proper divisors (1).

1397581 is an equidigital number, since it uses as much as digits as its factorization.

1397581 is an odious number, because the sum of its binary digits is odd.

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

The square root of 1397581 is about 1182.1933006070. The cubic root of 1397581 is about 111.8044259072.

The spelling of 1397581 in words is "one million, three hundred ninety-seven thousand, five hundred eighty-one".