138812500 has 42 divisors (see below), whose sum is σ = 303785174. Its totient is φ = 55500000.

The previous prime is 138812441. The next prime is 138812501. The reversal of 138812500 is 5218831.

It can be written as a sum of positive squares in 7 ways, for example, as 138344644 + 467856 = 11762^2 + 684^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138812501) by changing a digit.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 61390 + ... + 63610.

Almost surely, 2^138812500 is an apocalyptic number.

138812500 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 138812500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (151892587).

138812500 is an abundant number, since it is smaller than the sum of its proper divisors (164972674).

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

138812500 is an frugal number, since it uses more digits than its factorization.

138812500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2255 (or 2228 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 138812500 is about 11781.8716679482. The cubic root of 138812500 is about 517.7771236986. Note that the first 3 decimals are identical.

The spelling of 138812500 in words is "one hundred thirty-eight million, eight hundred twelve thousand, five hundred".