139448509 has 8 divisors (see below), whose sum is σ = 145771520. Its totient is φ = 133239600.

The previous prime is 139448497. The next prime is 139448521. The reversal of 139448509 is 905844931.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (139448497) and next prime (139448521).

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 139448509 - 2⁷ = 139448381 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139448539) 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, 26022 + ... + 30919.

It is an arithmetic number, because the mean of its divisors is an integer number (18221440).

Almost surely, 2^139448509 is an apocalyptic number.

It is an amenable number.

139448509 is a deficient number, since it is larger than the sum of its proper divisors (6323011).

139448509 is an equidigital number, since it uses as much as digits as its factorization.

139448509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57051.

The product of its (nonzero) digits is 155520, while the sum is 43.

The square root of 139448509 is about 11808.8318219882. The cubic root of 139448509 is about 518.5667001490.

The spelling of 139448509 in words is "one hundred thirty-nine million, four hundred forty-eight thousand, five hundred nine".