138005664 has 96 divisors (see below), whose sum is σ = 394632000. Its totient is φ = 42061824.

The previous prime is 138005641. The next prime is 138005687. The reversal of 138005664 is 466500831.

It is an interprime number because it is at equal distance from previous prime (138005641) and next prime (138005687).

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

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 15 ways as a sum of consecutive naturals, for example, 51592 + ... + 54200.

It is an arithmetic number, because the mean of its divisors is an integer number (4110750).

Almost surely, 2^138005664 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 138005664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (197316000).

138005664 is an abundant number, since it is smaller than the sum of its proper divisors (256626336).

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

138005664 is a wasteful number, since it uses less digits than its factorization.

138005664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2670 (or 2662 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 138005664 is about 11747.5811978466. The cubic root of 138005664 is about 516.7719950830.

The spelling of 138005664 in words is "one hundred thirty-eight million, five thousand, six hundred sixty-four".