138628272 has 20 divisors (see below), whose sum is σ = 358123160. Its totient is φ = 46209408.

The previous prime is 138628253. The next prime is 138628277. The reversal of 138628272 is 272826831.

It is a self number, because there is not a number n which added to its sum of digits gives 138628272.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138628277) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1443997 + ... + 1444092.

It is an arithmetic number, because the mean of its divisors is an integer number (17906158).

Almost surely, 2^138628272 is an apocalyptic number.

138628272 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

138628272 is an abundant number, since it is smaller than the sum of its proper divisors (219494888).

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

138628272 is a wasteful number, since it uses less digits than its factorization.

138628272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2888100 (or 2888094 counting only the distinct ones).

The product of its digits is 64512, while the sum is 39.

The square root of 138628272 is about 11774.0507897665. The cubic root of 138628272 is about 517.5479626017.

The spelling of 138628272 in words is "one hundred thirty-eight million, six hundred twenty-eight thousand, two hundred seventy-two".