139684289 has 2 divisors, whose sum is σ = 139684290. Its totient is φ = 139684288.

The previous prime is 139684277. The next prime is 139684331. The reversal of 139684289 is 982486931.

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., 124992400 + 14691889 = 11180^2 + 3833^2 .

It is a cyclic number.

It is not a de Polignac number, because 139684289 - 2⁴ = 139684273 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (139684249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69842144 + 69842145.

It is an arithmetic number, because the mean of its divisors is an integer number (69842145).

Almost surely, 2^139684289 is an apocalyptic number.

It is an amenable number.

139684289 is a deficient number, since it is larger than the sum of its proper divisors (1).

139684289 is an equidigital number, since it uses as much as digits as its factorization.

139684289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 746496, while the sum is 50.

The square root of 139684289 is about 11818.8108115834. The cubic root of 139684289 is about 518.8588003465.

It can be divided in two parts, 1396842 and 89, that added together give a palindrome (1396931).

The spelling of 139684289 in words is "one hundred thirty-nine million, six hundred eighty-four thousand, two hundred eighty-nine".