138809031 has 8 divisors (see below), whose sum is σ = 189383040. Its totient is φ = 90387192.

The previous prime is 138809023. The next prime is 138809057. The reversal of 138809031 is 130908831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 138809031 - 2³ = 138809023 is a prime.

It is a super-2 number, since 2×138809031² = 38535894174317922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 138808983 and 138809001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138809731) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 537891 + ... + 538148.

It is an arithmetic number, because the mean of its divisors is an integer number (23672880).

Almost surely, 2^138809031 is an apocalyptic number.

138809031 is a deficient number, since it is larger than the sum of its proper divisors (50574009).

138809031 is a wasteful number, since it uses less digits than its factorization.

138809031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1076085.

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 138809031 is about 11781.7244493325. The cubic root of 138809031 is about 517.7728104852.

The spelling of 138809031 in words is "one hundred thirty-eight million, eight hundred nine thousand, thirty-one".