138144780 has 36 divisors (see below), whose sum is σ = 419039712. Its totient is φ = 36838560.

The previous prime is 138144779. The next prime is 138144817. The reversal of 138144780 is 87441831.

138144780 is a `hidden beast` number, since 138 + 1 + 447 + 80 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 383556 + ... + 383915.

It is an arithmetic number, because the mean of its divisors is an integer number (11639992).

Almost surely, 2^138144780 is an apocalyptic number.

138144780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138144780 is an abundant number, since it is smaller than the sum of its proper divisors (280894932).

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

138144780 is a wasteful number, since it uses less digits than its factorization.

138144780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 767486 (or 767481 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 138144780 is about 11753.5007550942. The cubic root of 138144780 is about 516.9455800112.

The spelling of 138144780 in words is "one hundred thirty-eight million, one hundred forty-four thousand, seven hundred eighty".