138272730 has 64 divisors (see below), whose sum is σ = 354119040. Its totient is φ = 34433024.

The previous prime is 138272723. The next prime is 138272749. The reversal of 138272730 is 37272831.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 138272691 and 138272700.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 68881 + ... + 70859.

It is an arithmetic number, because the mean of its divisors is an integer number (5533110).

Almost surely, 2^138272730 is an apocalyptic number.

138272730 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 138272730, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (177059520).

138272730 is an abundant number, since it is smaller than the sum of its proper divisors (215846310).

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

138272730 is a wasteful number, since it uses less digits than its factorization.

138272730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2143.

The product of its (nonzero) digits is 14112, while the sum is 33.

The square root of 138272730 is about 11758.9425544987. The cubic root of 138272730 is about 517.1051294752.

The spelling of 138272730 in words is "one hundred thirty-eight million, two hundred seventy-two thousand, seven hundred thirty".