139969939 has 2 divisors, whose sum is σ = 139969940. Its totient is φ = 139969938.

The previous prime is 139969931. The next prime is 139969961. The reversal of 139969939 is 939969931.

139969939 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is an emirp because it is prime and its reverse (939969931) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 139969939 - 2³ = 139969931 is a prime.

It is not a weakly prime, because it can be changed into another prime (139969931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69984969 + 69984970.

It is an arithmetic number, because the mean of its divisors is an integer number (69984970).

Almost surely, 2^139969939 is an apocalyptic number.

139969939 is a deficient number, since it is larger than the sum of its proper divisors (1).

139969939 is an equidigital number, since it uses as much as digits as its factorization.

139969939 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3188646, while the sum is 58.

The square root of 139969939 is about 11830.8891888987. The cubic root of 139969939 is about 519.2122428664.

The spelling of 139969939 in words is "one hundred thirty-nine million, nine hundred sixty-nine thousand, nine hundred thirty-nine".