138581768 has 16 divisors (see below), whose sum is σ = 279828780. Its totient is φ = 63960768.

The previous prime is 138581759. The next prime is 138581791. The reversal of 138581768 is 867185831.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 128097124 + 10484644 = 11318^2 + 3238^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 666155 + ... + 666362.

Almost surely, 2^138581768 is an apocalyptic number.

It is an amenable number.

138581768 is an abundant number, since it is smaller than the sum of its proper divisors (141247012).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

138581768 is a wasteful number, since it uses less digits than its factorization.

138581768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1332536 (or 1332532 counting only the distinct ones).

The product of its digits is 322560, while the sum is 47.

The square root of 138581768 is about 11772.0757727769. The cubic root of 138581768 is about 517.4900842149.

The spelling of 138581768 in words is "one hundred thirty-eight million, five hundred eighty-one thousand, seven hundred sixty-eight".