12138939400 has 192 divisors, whose sum is σ = 33026457600. Its totient is φ = 4063530240.

The previous prime is 12138939347. The next prime is 12138939499. The reversal of 12138939400 is 493983121.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11912091 + ... + 11913109.

It is an arithmetic number, because the mean of its divisors is an integer number (172012800).

Almost surely, 2^12138939400 is an apocalyptic number.

12138939400 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 12138939400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16513228800).

12138939400 is an abundant number, since it is smaller than the sum of its proper divisors (20887518200).

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

12138939400 is a wasteful number, since it uses less digits than its factorization.

12138939400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1236 (or 1227 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 40.

The spelling of 12138939400 in words is "twelve billion, one hundred thirty-eight million, nine hundred thirty-nine thousand, four hundred".