43138639 has 16 divisors (see below), whose sum is σ = 49213440. Its totient is φ = 37572480.

The previous prime is 43138619. The next prime is 43138663. The reversal of 43138639 is 93683134.

It is a cyclic number.

It is not a de Polignac number, because 43138639 - 2⁹ = 43138127 is a prime.

It is a super-3 number, since 3×43138639³ (a number of 24 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 43138598 and 43138607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43138619) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10342 + ... + 13900.

It is an arithmetic number, because the mean of its divisors is an integer number (3075840).

Almost surely, 2^43138639 is an apocalyptic number.

43138639 is a deficient number, since it is larger than the sum of its proper divisors (6074801).

43138639 is a wasteful number, since it uses less digits than its factorization.

43138639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3630.

The product of its digits is 46656, while the sum is 37.

The square root of 43138639 is about 6568.0011419000. The cubic root of 43138639 is about 350.7159196329.

The spelling of 43138639 in words is "forty-three million, one hundred thirty-eight thousand, six hundred thirty-nine".