139163909 has 2 divisors, whose sum is σ = 139163910. Its totient is φ = 139163908.

The previous prime is 139163839. The next prime is 139163971. The reversal of 139163909 is 909361931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 70190884 + 68973025 = 8378^2 + 8305^2 .

It is an emirp because it is prime and its reverse (909361931) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 139163909 - 2²⁰ = 138115333 is a prime.

It is a Chen prime.

It is equal to p_7867517 and since 139163909 and 7867517 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (139163209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69581954 + 69581955.

It is an arithmetic number, because the mean of its divisors is an integer number (69581955).

Almost surely, 2^139163909 is an apocalyptic number.

It is an amenable number.

139163909 is a deficient number, since it is larger than the sum of its proper divisors (1).

139163909 is an equidigital number, since it uses as much as digits as its factorization.

139163909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 39366, while the sum is 41.

The square root of 139163909 is about 11796.7753644799. The cubic root of 139163909 is about 518.2136795271.

The spelling of 139163909 in words is "one hundred thirty-nine million, one hundred sixty-three thousand, nine hundred nine".