138978416 has 20 divisors (see below), whose sum is σ = 270630000. Its totient is φ = 69138432.

The previous prime is 138978391. The next prime is 138978421. The reversal of 138978416 is 614879831.

It is a super-2 number, since 2×138978416² = 38630000227738112, which contains 22 as substring.

It is a hoax number, since the sum of its digits (47) coincides with the sum of the digits of its distinct prime factors.

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, 18641 + ... + 25008.

It is an arithmetic number, because the mean of its divisors is an integer number (13531500).

Almost surely, 2^138978416 is an apocalyptic number.

138978416 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

138978416 is a deficient number, since it is larger than the sum of its proper divisors (131651584).

138978416 is a wasteful number, since it uses less digits than its factorization.

138978416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43856 (or 43850 counting only the distinct ones).

The product of its digits is 290304, while the sum is 47.

The square root of 138978416 is about 11788.9107215213. The cubic root of 138978416 is about 517.9833330455.

The spelling of 138978416 in words is "one hundred thirty-eight million, nine hundred seventy-eight thousand, four hundred sixteen".