139321639 has 2 divisors, whose sum is σ = 139321640. Its totient is φ = 139321638.

The previous prime is 139321619. The next prime is 139321697. The reversal of 139321639 is 936123931.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 139321639 - 2¹⁷ = 139190567 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 139321598 and 139321607.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (139321619) 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, 69660819 + 69660820.

It is an arithmetic number, because the mean of its divisors is an integer number (69660820).

Almost surely, 2^139321639 is an apocalyptic number.

139321639 is a deficient number, since it is larger than the sum of its proper divisors (1).

139321639 is an equidigital number, since it uses as much as digits as its factorization.

139321639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 26244, while the sum is 37.

The square root of 139321639 is about 11803.4587727496. The cubic root of 139321639 is about 518.4093887518.

It can be divided in two parts, 1393 and 21639, that added together give a palindrome (23032).

The spelling of 139321639 in words is "one hundred thirty-nine million, three hundred twenty-one thousand, six hundred thirty-nine".