139541309 has 2 divisors, whose sum is σ = 139541310. Its totient is φ = 139541308.

The previous prime is 139541291. The next prime is 139541333. The reversal of 139541309 is 903145931.

139541309 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 139169209 + 372100 = 11797^2 + 610^2 .

It is a cyclic number.

It is not a de Polignac number, because 139541309 - 2²⁰ = 138492733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (139541399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69770654 + 69770655.

It is an arithmetic number, because the mean of its divisors is an integer number (69770655).

Almost surely, 2^139541309 is an apocalyptic number.

It is an amenable number.

139541309 is a deficient number, since it is larger than the sum of its proper divisors (1).

139541309 is an equidigital number, since it uses as much as digits as its factorization.

139541309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14580, while the sum is 35.

The square root of 139541309 is about 11812.7604309916. The cubic root of 139541309 is about 518.6817063238.

The spelling of 139541309 in words is "one hundred thirty-nine million, five hundred forty-one thousand, three hundred nine".