1366689 has 8 divisors (see below), whose sum is σ = 1918240. Its totient is φ = 863136.

The previous prime is 1366667. The next prime is 1366693. The reversal of 1366689 is 9866631.

1366689 = 267² + 268² + ... + 284².

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1366689 - 2⁵ = 1366657 is a prime.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (1366609) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11932 + ... + 12045.

It is an arithmetic number, because the mean of its divisors is an integer number (239780).

2^1366689 is an apocalyptic number.

1366689 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1366689 is a deficient number, since it is larger than the sum of its proper divisors (551551).

1366689 is a wasteful number, since it uses less digits than its factorization.

1366689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23999.

The product of its digits is 46656, while the sum is 39.

The square root of 1366689 is about 1169.0547463656. The cubic root of 1366689 is about 110.9745092022.

The spelling of 1366689 in words is "one million, three hundred sixty-six thousand, six hundred eighty-nine".