138628733 has 4 divisors (see below), whose sum is σ = 139026300. Its totient is φ = 138231168.

The previous prime is 138628717. The next prime is 138628741. The reversal of 138628733 is 337826831.

138628733 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 337826831 = 79 ⋅4276289.

It can be written as a sum of positive squares in 2 ways, for example, as 96079204 + 42549529 = 9802^2 + 6523^2 .

It is a cyclic number.

It is not a de Polignac number, because 138628733 - 2⁴ = 138628717 is a prime.

It is a super-2 number, since 2×138628733² = 38435851226370578, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138628753) 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, 198260 + ... + 198957.

It is an arithmetic number, because the mean of its divisors is an integer number (34756575).

Almost surely, 2^138628733 is an apocalyptic number.

It is an amenable number.

138628733 is a deficient number, since it is larger than the sum of its proper divisors (397567).

138628733 is an equidigital number, since it uses as much as digits as its factorization.

138628733 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397566.

The product of its digits is 145152, while the sum is 41.

The square root of 138628733 is about 11774.0703666999. The cubic root of 138628733 is about 517.5485362926.

The spelling of 138628733 in words is "one hundred thirty-eight million, six hundred twenty-eight thousand, seven hundred thirty-three".