1399381 has 2 divisors, whose sum is σ = 1399382. Its totient is φ = 1399380.

The previous prime is 1399373. The next prime is 1399393. The reversal of 1399381 is 1839931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1232100 + 167281 = 1110^2 + 409^2 .

It is a cyclic number.

It is not a de Polignac number, because 1399381 - 2³ = 1399373 is a prime.

It is a super-2 number, since 2×1399381² = 3916534366322, which contains 22 as substring.

It is a zygodrome in base 4.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1399301) 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, 699690 + 699691.

It is an arithmetic number, because the mean of its divisors is an integer number (699691).

2^1399381 is an apocalyptic number.

It is an amenable number.

1399381 is a deficient number, since it is larger than the sum of its proper divisors (1).

1399381 is an equidigital number, since it uses as much as digits as its factorization.

1399381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5832, while the sum is 34.

The square root of 1399381 is about 1182.9543524583. The cubic root of 1399381 is about 111.8524044335.

The spelling of 1399381 in words is "one million, three hundred ninety-nine thousand, three hundred eighty-one".