138629972 has 24 divisors (see below), whose sum is σ = 268329096. Its totient is φ = 62252928.

The previous prime is 138629969. The next prime is 138629983. The reversal of 138629972 is 279926831.

It is a happy number.

138629972 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 4857616 + 133772356 = 2204^2 + 11566^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34103 + ... + 37950.

It is an arithmetic number, because the mean of its divisors is an integer number (11180379).

Almost surely, 2^138629972 is an apocalyptic number.

It is an amenable number.

138629972 is a deficient number, since it is larger than the sum of its proper divisors (129699124).

138629972 is a wasteful number, since it uses less digits than its factorization.

138629972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72107 (or 72105 counting only the distinct ones).

The product of its digits is 326592, while the sum is 47.

The square root of 138629972 is about 11774.1229822013. The cubic root of 138629972 is about 517.5500781585.

The spelling of 138629972 in words is "one hundred thirty-eight million, six hundred twenty-nine thousand, nine hundred seventy-two".