138810643 has 4 divisors (see below), whose sum is σ = 142562320. Its totient is φ = 135058968.

The previous prime is 138810631. The next prime is 138810649. The reversal of 138810643 is 346018831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 346018831 = 23 ⋅15044297.

It is a cyclic number.

It is not a de Polignac number, because 138810643 - 2¹³ = 138802451 is a prime.

It is a super-2 number, since 2×138810643² = 38536789220146898, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 138810599 and 138810608.

It is not an unprimeable number, because it can be changed into a prime (138810649) 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, 1875783 + ... + 1875856.

It is an arithmetic number, because the mean of its divisors is an integer number (35640580).

Almost surely, 2^138810643 is an apocalyptic number.

138810643 is a deficient number, since it is larger than the sum of its proper divisors (3751677).

138810643 is an equidigital number, since it uses as much as digits as its factorization.

138810643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3751676.

The product of its (nonzero) digits is 13824, while the sum is 34.

The square root of 138810643 is about 11781.7928601720. The cubic root of 138810643 is about 517.7748147893.

The spelling of 138810643 in words is "one hundred thirty-eight million, eight hundred ten thousand, six hundred forty-three".