139980209 has 2 divisors, whose sum is σ = 139980210. Its totient is φ = 139980208.

The previous prime is 139980133. The next prime is 139980223. The reversal of 139980209 is 902089931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 91259809 + 48720400 = 9553^2 + 6980^2 .

It is a cyclic number.

It is not a de Polignac number, because 139980209 - 2²⁴ = 123202993 is a prime.

It is not a weakly prime, because it can be changed into another prime (139980229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69990104 + 69990105.

It is an arithmetic number, because the mean of its divisors is an integer number (69990105).

Almost surely, 2^139980209 is an apocalyptic number.

It is an amenable number.

139980209 is a deficient number, since it is larger than the sum of its proper divisors (1).

139980209 is an equidigital number, since it uses as much as digits as its factorization.

139980209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34992, while the sum is 41.

The square root of 139980209 is about 11831.3232142478. The cubic root of 139980209 is about 519.2249412581.

The spelling of 139980209 in words is "one hundred thirty-nine million, nine hundred eighty thousand, two hundred nine".