1339781 has 2 divisors, whose sum is σ = 1339782. Its totient is φ = 1339780.

The previous prime is 1339777. The next prime is 1339813. The reversal of 1339781 is 1879331.

It is an a-pointer prime, because the next prime (1339813) can be obtained adding 1339781 to its sum of digits (32).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 801025 + 538756 = 895^2 + 734^2 .

It is a cyclic number.

It is not a de Polignac number, because 1339781 - 2² = 1339777 is a prime.

It is a super-2 number, since 2×1339781² = 3590026255922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1339711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 669890 + 669891.

It is an arithmetic number, because the mean of its divisors is an integer number (669891).

2^1339781 is an apocalyptic number.

It is an amenable number.

1339781 is a deficient number, since it is larger than the sum of its proper divisors (1).

1339781 is an equidigital number, since it uses as much as digits as its factorization.

1339781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4536, while the sum is 32.

The square root of 1339781 is about 1157.4890928212. The cubic root of 1339781 is about 110.2413708039.

The spelling of 1339781 in words is "one million, three hundred thirty-nine thousand, seven hundred eighty-one".