138633860 has 36 divisors (see below), whose sum is σ = 300867084. Its totient is φ = 53657280.

The previous prime is 138633853. The next prime is 138633871. The reversal of 138633860 is 68336831.

It can be written as a sum of positive squares in 2 ways, for example, as 84198976 + 54434884 = 9176^2 + 7378^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15614 + ... + 22826.

It is an arithmetic number, because the mean of its divisors is an integer number (8357419).

Almost surely, 2^138633860 is an apocalyptic number.

138633860 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 138633860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (150433542).

138633860 is an abundant number, since it is smaller than the sum of its proper divisors (162233224).

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

138633860 is a wasteful number, since it uses less digits than its factorization.

138633860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7284 (or 7251 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 38.

The square root of 138633860 is about 11774.2880888825. The cubic root of 138633860 is about 517.5549164962.

The spelling of 138633860 in words is "one hundred thirty-eight million, six hundred thirty-three thousand, eight hundred sixty".