138722440428 has 192 divisors, whose sum is σ = 423325002240. Its totient is φ = 38730182400.

The previous prime is 138722440391. The next prime is 138722440433. The reversal of 138722440428 is 824044227831.

138722440428 is a `hidden beast` number, since 1 + 387 + 2 + 244 + 0 + 4 + 28 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8439658 + ... + 8456078.

It is an arithmetic number, because the mean of its divisors is an integer number (2204817720).

Almost surely, 2^138722440428 is an apocalyptic number.

138722440428 is a gapful number since it is divisible by the number (18) 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 138722440428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (211662501120).

138722440428 is an abundant number, since it is smaller than the sum of its proper divisors (284602561812).

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

138722440428 is a wasteful number, since it uses less digits than its factorization.

138722440428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17005 (or 16997 counting only the distinct ones).

The product of its (nonzero) digits is 688128, while the sum is 45.

The spelling of 138722440428 in words is "one hundred thirty-eight billion, seven hundred twenty-two million, four hundred forty thousand, four hundred twenty-eight".