138849571 has 4 divisors (see below), whose sum is σ = 158685232. Its totient is φ = 119013912.

The previous prime is 138849569. The next prime is 138849671. The reversal of 138849571 is 175948831.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 138849571 - 2¹ = 138849569 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138849521) 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, 9917820 + ... + 9917833.

It is an arithmetic number, because the mean of its divisors is an integer number (39671308).

Almost surely, 2^138849571 is an apocalyptic number.

138849571 is a deficient number, since it is larger than the sum of its proper divisors (19835661).

138849571 is an equidigital number, since it uses as much as digits as its factorization.

138849571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19835660.

The product of its digits is 241920, while the sum is 46.

The square root of 138849571 is about 11783.4447849515. Note that the first 3 decimals coincide. The cubic root of 138849571 is about 517.8232117846.

The spelling of 138849571 in words is "one hundred thirty-eight million, eight hundred forty-nine thousand, five hundred seventy-one".