139844209 has 8 divisors (see below), whose sum is σ = 148104000. Its totient is φ = 131766096.

The previous prime is 139844207. The next prime is 139844239. The reversal of 139844209 is 902448931.

139844209 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 139844209 - 2¹ = 139844207 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (139844207) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43834 + ... + 46915.

It is an arithmetic number, because the mean of its divisors is an integer number (18513000).

Almost surely, 2^139844209 is an apocalyptic number.

It is an amenable number.

139844209 is a deficient number, since it is larger than the sum of its proper divisors (8259791).

139844209 is an equidigital number, since it uses as much as digits as its factorization.

139844209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90839.

The product of its (nonzero) digits is 62208, while the sum is 40.

The square root of 139844209 is about 11825.5743623724. The cubic root of 139844209 is about 519.0567330193.

The spelling of 139844209 in words is "one hundred thirty-nine million, eight hundred forty-four thousand, two hundred nine".