139392609 has 4 divisors (see below), whose sum is σ = 185856816. Its totient is φ = 92928404.

The previous prime is 139392593. The next prime is 139392613. The reversal of 139392609 is 906293931.

It is a happy number.

139392609 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 906293931 = 3 ⋅302097977.

It is a cyclic number.

It is not a de Polignac number, because 139392609 - 2⁴ = 139392593 is a prime.

It is not an unprimeable number, because it can be changed into a prime (139392689) 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, 23232099 + ... + 23232104.

It is an arithmetic number, because the mean of its divisors is an integer number (46464204).

Almost surely, 2^139392609 is an apocalyptic number.

It is an amenable number.

139392609 is a deficient number, since it is larger than the sum of its proper divisors (46464207).

139392609 is an equidigital number, since it uses as much as digits as its factorization.

139392609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46464206.

The product of its (nonzero) digits is 78732, while the sum is 42.

The square root of 139392609 is about 11806.4647121821. The cubic root of 139392609 is about 518.4973991743.

The spelling of 139392609 in words is "one hundred thirty-nine million, three hundred ninety-two thousand, six hundred nine".