138651968 has 168 divisors, whose sum is σ = 364845600. Its totient is φ = 51674112.

The previous prime is 138651959. The next prime is 138651977. The reversal of 138651968 is 869156831.

It is an interprime number because it is at equal distance from previous prime (138651959) and next prime (138651977).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 774503 + ... + 774681.

It is an arithmetic number, because the mean of its divisors is an integer number (2171700).

Almost surely, 2^138651968 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138651968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (182422800).

138651968 is an abundant number, since it is smaller than the sum of its proper divisors (226193632).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

138651968 is a wasteful number, since it uses less digits than its factorization.

138651968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237 (or 220 counting only the distinct ones).

The product of its digits is 311040, while the sum is 47.

The square root of 138651968 is about 11775.0570274628. The cubic root of 138651968 is about 517.5774494148.

The spelling of 138651968 in words is "one hundred thirty-eight million, six hundred fifty-one thousand, nine hundred sixty-eight".