138261055780 has 24 divisors (see below), whose sum is σ = 291427589880. Its totient is φ = 55098827520.

The previous prime is 138261055769. The next prime is 138261055789. The reversal of 138261055780 is 87550162831.

It can be written as a sum of positive squares in 4 ways, for example, as 20029608676 + 118231447104 = 141526^2 + 343848^2 .

It is a super-2 number, since 2×138261055780² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 138261055780.

It is not an unprimeable number, because it can be changed into a prime (138261055789) 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, 12844161 + ... + 12854920.

It is an arithmetic number, because the mean of its divisors is an integer number (12142816245).

Almost surely, 2^138261055780 is an apocalyptic number.

138261055780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138261055780 is an abundant number, since it is smaller than the sum of its proper divisors (153166534100).

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

138261055780 is a wasteful number, since it uses less digits than its factorization.

138261055780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25699359 (or 25699357 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 46.

The spelling of 138261055780 in words is "one hundred thirty-eight billion, two hundred sixty-one million, fifty-five thousand, seven hundred eighty".