138809663 has 4 divisors (see below), whose sum is σ = 138845880. Its totient is φ = 138773448.

The previous prime is 138809621. The next prime is 138809677. The reversal of 138809663 is 366908831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 366908831 = 991 ⋅370241.

It is a cyclic number.

It is not a de Polignac number, because 138809663 - 2¹² = 138805567 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138809683) 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, 11573 + ... + 20286.

It is an arithmetic number, because the mean of its divisors is an integer number (34711470).

Almost surely, 2^138809663 is an apocalyptic number.

138809663 is a deficient number, since it is larger than the sum of its proper divisors (36217).

138809663 is an equidigital number, since it uses as much as digits as its factorization.

138809663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36216.

The product of its (nonzero) digits is 186624, while the sum is 44.

The square root of 138809663 is about 11781.7512705030. The cubic root of 138809663 is about 517.7735962936.

The spelling of 138809663 in words is "one hundred thirty-eight million, eight hundred nine thousand, six hundred sixty-three".