138403680 has 96 divisors (see below), whose sum is σ = 447812064. Its totient is φ = 35905536.

The previous prime is 138403669. The next prime is 138403691. The reversal of 138403680 is 86304831.

138403680 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (138403669) and next prime (138403691).

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13864 + ... + 21656.

It is an arithmetic number, because the mean of its divisors is an integer number (4664709).

Almost surely, 2^138403680 is an apocalyptic number.

138403680 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 138403680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (223906032).

138403680 is an abundant number, since it is smaller than the sum of its proper divisors (309408384).

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

138403680 is a wasteful number, since it uses less digits than its factorization.

138403680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7848 (or 7840 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 138403680 is about 11764.5093395347. The cubic root of 138403680 is about 517.2683179594.

The spelling of 138403680 in words is "one hundred thirty-eight million, four hundred three thousand, six hundred eighty".