1381993 has 2 divisors, whose sum is σ = 1381994. Its totient is φ = 1381992.

The previous prime is 1381979. The next prime is 1381997. The reversal of 1381993 is 3991831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1065024 + 316969 = 1032^2 + 563^2 .

It is an emirp because it is prime and its reverse (3991831) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1381993 is a prime.

It is not a weakly prime, because it can be changed into another prime (1381997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 690996 + 690997.

It is an arithmetic number, because the mean of its divisors is an integer number (690997).

2^1381993 is an apocalyptic number.

It is an amenable number.

1381993 is a deficient number, since it is larger than the sum of its proper divisors (1).

1381993 is an equidigital number, since it uses as much as digits as its factorization.

1381993 is an evil number, because the sum of its binary digits is even.

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

The square root of 1381993 is about 1175.5819835299. The cubic root of 1381993 is about 111.3871984877.

The spelling of 1381993 in words is "one million, three hundred eighty-one thousand, nine hundred ninety-three".