138787680 has 48 divisors (see below), whose sum is σ = 437182704. Its totient is φ = 37009920.

The previous prime is 138787679. The next prime is 138787687. The reversal of 138787680 is 86787831.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138787687) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 144091 + ... + 145050.

It is an arithmetic number, because the mean of its divisors is an integer number (9107973).

Almost surely, 2^138787680 is an apocalyptic number.

138787680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138787680 is an abundant number, since it is smaller than the sum of its proper divisors (298395024).

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

138787680 is a wasteful number, since it uses less digits than its factorization.

138787680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 289159 (or 289151 counting only the distinct ones).

The product of its (nonzero) digits is 451584, while the sum is 48.

The square root of 138787680 is about 11780.8183077408. The cubic root of 138787680 is about 517.7462619385.

The spelling of 138787680 in words is "one hundred thirty-eight million, seven hundred eighty-seven thousand, six hundred eighty".