138329287 has 4 divisors (see below), whose sum is σ = 138607000. Its totient is φ = 138051576.

The previous prime is 138329251. The next prime is 138329299. The reversal of 138329287 is 782923831.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 138329287 - 2¹⁹ = 137804999 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 (138329687) 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, 138108 + ... + 139105.

It is an arithmetic number, because the mean of its divisors is an integer number (34651750).

Almost surely, 2^138329287 is an apocalyptic number.

138329287 is a deficient number, since it is larger than the sum of its proper divisors (277713).

138329287 is an equidigital number, since it uses as much as digits as its factorization.

138329287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277712.

The product of its digits is 145152, while the sum is 43.

The square root of 138329287 is about 11761.3471592331. The cubic root of 138329287 is about 517.1756228358.

The spelling of 138329287 in words is "one hundred thirty-eight million, three hundred twenty-nine thousand, two hundred eighty-seven".