1366641289 has 4 divisors (see below), whose sum is σ = 1471767556. Its totient is φ = 1261515024.

The previous prime is 1366641281. The next prime is 1366641307. The reversal of 1366641289 is 9821466631.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9821466631 = 21683 ⋅452957.

It can be written as a sum of positive squares in 2 ways, for example, as 610831225 + 755810064 = 24715^2 + 27492^2 .

It is a cyclic number.

It is not a de Polignac number, because 1366641289 - 2³ = 1366641281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1366641281) 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, 52563114 + ... + 52563139.

It is an arithmetic number, because the mean of its divisors is an integer number (367941889).

Almost surely, 2^1366641289 is an apocalyptic number.

It is an amenable number.

1366641289 is a deficient number, since it is larger than the sum of its proper divisors (105126267).

1366641289 is a wasteful number, since it uses less digits than its factorization.

1366641289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105126266.

The product of its digits is 373248, while the sum is 46.

The square root of 1366641289 is about 36968.1117856998. Note that the first 3 decimals coincide. The cubic root of 1366641289 is about 1109.7321781682.

The spelling of 1366641289 in words is "one billion, three hundred sixty-six million, six hundred forty-one thousand, two hundred eighty-nine".