138664406 has 8 divisors (see below), whose sum is σ = 211101240. Its totient is φ = 68297328.

The previous prime is 138664397. The next prime is 138664433. The reversal of 138664406 is 604466831.

138664406 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a super-3 number, since 3×138664406³ (a number of 25 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 138664406.

It is a congruent number.

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, 517271 + ... + 517538.

It is an arithmetic number, because the mean of its divisors is an integer number (26387655).

Almost surely, 2^138664406 is an apocalyptic number.

138664406 is a deficient number, since it is larger than the sum of its proper divisors (72436834).

138664406 is a wasteful number, since it uses less digits than its factorization.

138664406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1034878.

The product of its (nonzero) digits is 82944, while the sum is 38.

The square root of 138664406 is about 11775.5851659270. The cubic root of 138664406 is about 517.5929256606.

The spelling of 138664406 in words is "one hundred thirty-eight million, six hundred sixty-four thousand, four hundred six".