1366789 has 4 divisors (see below), whose sum is σ = 1372140. Its totient is φ = 1361440.

The previous prime is 1366769. The next prime is 1366793. The reversal of 1366789 is 9876631.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9876631 = 31 ⋅318601.

It can be written as a sum of positive squares in 2 ways, for example, as 134689 + 1232100 = 367^2 + 1110^2 .

It is a cyclic number.

It is not a de Polignac number, because 1366789 - 2⁷ = 1366661 is a prime.

It is a super-2 number, since 2×1366789² = 3736224341042, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1366709) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2272 + ... + 2809.

It is an arithmetic number, because the mean of its divisors is an integer number (343035).

2^1366789 is an apocalyptic number.

It is an amenable number.

1366789 is a deficient number, since it is larger than the sum of its proper divisors (5351).

1366789 is an equidigital number, since it uses as much as digits as its factorization.

1366789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5350.

The product of its digits is 54432, while the sum is 40.

The square root of 1366789 is about 1169.0975151800. The cubic root of 1366789 is about 110.9772157873.

The spelling of 1366789 in words is "one million, three hundred sixty-six thousand, seven hundred eighty-nine".