138244320 has 120 divisors (see below), whose sum is σ = 487932984. Its totient is φ = 36861696.

The previous prime is 138244307. The next prime is 138244339. The reversal of 138244320 is 23442831.

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×138244320² = 38222984024524800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 7627 + ... + 18293.

Almost surely, 2^138244320 is an apocalyptic number.

138244320 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 138244320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (243966492).

138244320 is an abundant number, since it is smaller than the sum of its proper divisors (349688664).

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

138244320 is a wasteful number, since it uses less digits than its factorization.

138244320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10694 (or 10677 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The square root of 138244320 is about 11757.7344756547. The cubic root of 138244320 is about 517.0697116383.

The spelling of 138244320 in words is "one hundred thirty-eight million, two hundred forty-four thousand, three hundred twenty".