138869280 has 216 divisors, whose sum is σ = 521542476. Its totient is φ = 33623040.

The previous prime is 138869279. The next prime is 138869321. The reversal of 138869280 is 82968831.

It can be written as a sum of positive squares in 2 ways, for example, as 138015504 + 853776 = 11748^2 + 924^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

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 35 ways as a sum of consecutive naturals, for example, 173842 + ... + 174638.

Almost surely, 2^138869280 is an apocalyptic number.

138869280 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 138869280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (260771238).

138869280 is an abundant number, since it is smaller than the sum of its proper divisors (382673196).

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

138869280 is a wasteful number, since it uses less digits than its factorization.

138869280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 840 (or 818 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The square root of 138869280 is about 11784.2810557115. The cubic root of 138869280 is about 517.8477114278.

The spelling of 138869280 in words is "one hundred thirty-eight million, eight hundred sixty-nine thousand, two hundred eighty".