138721760 has 24 divisors (see below), whose sum is σ = 327730536. Its totient is φ = 55488640.

The previous prime is 138721721. The next prime is 138721777. The reversal of 138721760 is 67127831.

It is a self number, because there is not a number n which added to its sum of digits gives 138721760.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 433346 + ... + 433665.

It is an arithmetic number, because the mean of its divisors is an integer number (13655439).

Almost surely, 2^138721760 is an apocalyptic number.

138721760 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138721760 is an abundant number, since it is smaller than the sum of its proper divisors (189008776).

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

138721760 is an equidigital number, since it uses as much as digits as its factorization.

138721760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 867026 (or 867018 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 35.

The square root of 138721760 is about 11778.0202071486. The cubic root of 138721760 is about 517.6642776236.

The spelling of 138721760 in words is "one hundred thirty-eight million, seven hundred twenty-one thousand, seven hundred sixty".