139631669 has 2 divisors, whose sum is σ = 139631670. Its totient is φ = 139631668.

The previous prime is 139631629. The next prime is 139631717. The reversal of 139631669 is 966136931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 132135025 + 7496644 = 11495^2 + 2738^2 .

It is an emirp because it is prime and its reverse (966136931) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-139631669 is a prime.

It is a super-2 number, since 2×139631669² = 38994005975451122, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (139631629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69815834 + 69815835.

It is an arithmetic number, because the mean of its divisors is an integer number (69815835).

Almost surely, 2^139631669 is an apocalyptic number.

It is an amenable number.

139631669 is a deficient number, since it is larger than the sum of its proper divisors (1).

139631669 is an equidigital number, since it uses as much as digits as its factorization.

139631669 is an evil number, because the sum of its binary digits is even.

The product of its digits is 157464, while the sum is 44.

The square root of 139631669 is about 11816.5844896061. The cubic root of 139631669 is about 518.7936396442.

The spelling of 139631669 in words is "one hundred thirty-nine million, six hundred thirty-one thousand, six hundred sixty-nine".