1366728638 has 12 divisors (see below), whose sum is σ = 2253408360. Its totient is φ = 621240180.

The previous prime is 1366728631. The next prime is 1366728683. The reversal of 1366728638 is 8368276631.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1366728631) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2823578 + ... + 2824061.

It is an arithmetic number, because the mean of its divisors is an integer number (187784030).

Almost surely, 2^1366728638 is an apocalyptic number.

1366728638 is a deficient number, since it is larger than the sum of its proper divisors (886679722).

1366728638 is a wasteful number, since it uses less digits than its factorization.

1366728638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5647663 (or 5647652 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 50.

The square root of 1366728638 is about 36969.2931769056. The cubic root of 1366728638 is about 1109.7558205416.

The spelling of 1366728638 in words is "one billion, three hundred sixty-six million, seven hundred twenty-eight thousand, six hundred thirty-eight".