138397680 has 160 divisors (see below), whose sum is σ = 504878400. Its totient is φ = 34725888.

The previous prime is 138397667. The next prime is 138397687. The reversal of 138397680 is 86793831.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138397687) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 34836 + ... + 38604.

It is an arithmetic number, because the mean of its divisors is an integer number (3155490).

Almost surely, 2^138397680 is an apocalyptic number.

138397680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138397680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (252439200).

138397680 is an abundant number, since it is smaller than the sum of its proper divisors (366480720).

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

138397680 is a wasteful number, since it uses less digits than its factorization.

138397680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3808 (or 3796 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The square root of 138397680 is about 11764.2543325108. The cubic root of 138397680 is about 517.2608430745.

The spelling of 138397680 in words is "one hundred thirty-eight million, three hundred ninety-seven thousand, six hundred eighty".