139356221 has 2 divisors, whose sum is σ = 139356222. Its totient is φ = 139356220.

The previous prime is 139356193. The next prime is 139356251. The reversal of 139356221 is 122653931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 96924025 + 42432196 = 9845^2 + 6514^2 .

It is a cyclic number.

It is not a de Polignac number, because 139356221 - 2¹⁰ = 139355197 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (139356251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69678110 + 69678111.

It is an arithmetic number, because the mean of its divisors is an integer number (69678111).

Almost surely, 2^139356221 is an apocalyptic number.

It is an amenable number.

139356221 is a deficient number, since it is larger than the sum of its proper divisors (1).

139356221 is an equidigital number, since it uses as much as digits as its factorization.

139356221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9720, while the sum is 32.

The square root of 139356221 is about 11804.9235914512. The cubic root of 139356221 is about 518.4522778787.

The spelling of 139356221 in words is "one hundred thirty-nine million, three hundred fifty-six thousand, two hundred twenty-one".