138378646 has 24 divisors (see below), whose sum is σ = 243818640. Its totient is φ = 58725072.

The previous prime is 138378619. The next prime is 138378671. The reversal of 138378646 is 646873831.

It is a junction number, because it is equal to n+sod(n) for n = 138378596 and 138378605.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3240 + ... + 16948.

It is an arithmetic number, because the mean of its divisors is an integer number (10159110).

Almost surely, 2^138378646 is an apocalyptic number.

138378646 is a deficient number, since it is larger than the sum of its proper divisors (105439994).

138378646 is a wasteful number, since it uses less digits than its factorization.

138378646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13828 (or 13821 counting only the distinct ones).

The product of its digits is 580608, while the sum is 46.

The square root of 138378646 is about 11763.4453286442. The cubic root of 138378646 is about 517.2371288179.

The spelling of 138378646 in words is "one hundred thirty-eight million, three hundred seventy-eight thousand, six hundred forty-six".