139862209 has 2 divisors, whose sum is σ = 139862210. Its totient is φ = 139862208.

The previous prime is 139862207. The next prime is 139862237. The reversal of 139862209 is 902268931.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 127238400 + 12623809 = 11280^2 + 3553^2 .

It is a cyclic number.

It is not a de Polignac number, because 139862209 - 2¹ = 139862207 is a prime.

It is a super-2 number, since 2×139862209² = 39122875012719362, which contains 22 as substring.

Together with 139862207, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (139862201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69931104 + 69931105.

It is an arithmetic number, because the mean of its divisors is an integer number (69931105).

Almost surely, 2^139862209 is an apocalyptic number.

It is an amenable number.

139862209 is a deficient number, since it is larger than the sum of its proper divisors (1).

139862209 is an equidigital number, since it uses as much as digits as its factorization.

139862209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46656, while the sum is 40.

The square root of 139862209 is about 11826.3354002836. The cubic root of 139862209 is about 519.0790021344.

The spelling of 139862209 in words is "one hundred thirty-nine million, eight hundred sixty-two thousand, two hundred nine".