138785918280 has 256 divisors, whose sum is σ = 450161971200. Its totient is φ = 34125020160.

The previous prime is 138785918279. The next prime is 138785918281. The reversal of 138785918280 is 82819587831.

It is an interprime number because it is at equal distance from previous prime (138785918279) and next prime (138785918281).

It is a super-2 number, since 2×138785918280² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is not an unprimeable number, because it can be changed into a prime (138785918281) by changing a digit.

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 63 ways as a sum of consecutive naturals, for example, 75796965 + ... + 75798795.

It is an arithmetic number, because the mean of its divisors is an integer number (1758445200).

Almost surely, 2^138785918280 is an apocalyptic number.

138785918280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 138785918280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (225080985600).

138785918280 is an abundant number, since it is smaller than the sum of its proper divisors (311376052920).

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

138785918280 is a wasteful number, since it uses less digits than its factorization.

138785918280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2844 (or 2840 counting only the distinct ones).

The product of its (nonzero) digits is 7741440, while the sum is 60.

The spelling of 138785918280 in words is "one hundred thirty-eight billion, seven hundred eighty-five million, nine hundred eighteen thousand, two hundred eighty".