138840100 has 72 divisors (see below), whose sum is σ = 346172288. Its totient is φ = 47347200.

The previous prime is 138840073. The next prime is 138840109. The reversal of 138840100 is 1048831.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (138840109) 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, 168289 + ... + 169111.

Almost surely, 2^138840100 is an apocalyptic number.

138840100 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 138840100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (173086144).

138840100 is an abundant number, since it is smaller than the sum of its proper divisors (207332188).

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

138840100 is a wasteful number, since it uses less digits than its factorization.

138840100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1085 (or 1078 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 138840100 is about 11783.0429007112. The cubic root of 138840100 is about 517.8114378552.

Adding to 138840100 its reverse (1048831), we get a palindrome (139888931).

The spelling of 138840100 in words is "one hundred thirty-eight million, eight hundred forty thousand, one hundred".