138865471 has 4 divisors (see below), whose sum is σ = 146174200. Its totient is φ = 131556744.

The previous prime is 138865457. The next prime is 138865501. The reversal of 138865471 is 174568831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 174568831 = 1789 ⋅97579.

It is a cyclic number.

It is not a de Polignac number, because 138865471 - 2²¹ = 136768319 is a prime.

It is a super-3 number, since 3×138865471³ (a number of 25 digits) contains 333 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 (138865451) 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, 3654336 + ... + 3654373.

It is an arithmetic number, because the mean of its divisors is an integer number (36543550).

Almost surely, 2^138865471 is an apocalyptic number.

138865471 is a deficient number, since it is larger than the sum of its proper divisors (7308729).

138865471 is an equidigital number, since it uses as much as digits as its factorization.

138865471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7308728.

The product of its digits is 161280, while the sum is 43.

The square root of 138865471 is about 11784.1194410104. The cubic root of 138865471 is about 517.8429767594.

The spelling of 138865471 in words is "one hundred thirty-eight million, eight hundred sixty-five thousand, four hundred seventy-one".