138640346 has 8 divisors (see below), whose sum is σ = 223957524. Its totient is φ = 63987840.

The previous prime is 138640331. The next prime is 138640349. The reversal of 138640346 is 643046831.

It can be written as a sum of positive squares in 2 ways, for example, as 138321121 + 319225 = 11761^2 + 565^2 .

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

It is a super-2 number, since 2×138640346² = 38442291077999432, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (138640349) 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, 2666135 + ... + 2666186.

Almost surely, 2^138640346 is an apocalyptic number.

138640346 is a deficient number, since it is larger than the sum of its proper divisors (85317178).

138640346 is a wasteful number, since it uses less digits than its factorization.

138640346 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5332336.

The product of its (nonzero) digits is 41472, while the sum is 35.

The square root of 138640346 is about 11774.5635163262. The cubic root of 138640346 is about 517.5629876578.

The spelling of 138640346 in words is "one hundred thirty-eight million, six hundred forty thousand, three hundred forty-six".