138363408 has 120 divisors (see below), whose sum is σ = 424359000. Its totient is φ = 41889792.

The previous prime is 138363371. The next prime is 138363409. The reversal of 138363408 is 804363831.

It is a happy number.

138363408 is a `hidden beast` number, since 13 + 8 + 3 + 634 + 0 + 8 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 59721984 + 78641424 = 7728^2 + 8868^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138363409) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 70018 + ... + 71966.

It is an arithmetic number, because the mean of its divisors is an integer number (3536325).

Almost surely, 2^138363408 is an apocalyptic number.

138363408 is a gapful number since it is divisible by the number (18) 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 138363408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (212179500).

138363408 is an abundant number, since it is smaller than the sum of its proper divisors (285995592).

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

138363408 is a wasteful number, since it uses less digits than its factorization.

138363408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2009 (or 2000 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

The square root of 138363408 is about 11762.7976264152. The cubic root of 138363408 is about 517.2181423897.

The spelling of 138363408 in words is "one hundred thirty-eight million, three hundred sixty-three thousand, four hundred eight".