138849637920 has 960 divisors, whose sum is σ = 570215479680. Its totient is φ = 28222193664.

The previous prime is 138849637919. The next prime is 138849637961. The reversal of 138849637920 is 29736948831.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 372250854 + ... + 372251226.

It is an arithmetic number, because the mean of its divisors is an integer number (593974458).

Almost surely, 2^138849637920 is an apocalyptic number.

138849637920 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 138849637920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (285107739840).

138849637920 is an abundant number, since it is smaller than the sum of its proper divisors (431365841760).

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

138849637920 is a wasteful number, since it uses less digits than its factorization.

138849637920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 455 (or 426 counting only the distinct ones).

The product of its (nonzero) digits is 15676416, while the sum is 60.

The spelling of 138849637920 in words is "one hundred thirty-eight billion, eight hundred forty-nine million, six hundred thirty-seven thousand, nine hundred twenty".