139967939 has 2 divisors, whose sum is σ = 139967940. Its totient is φ = 139967938.

The previous prime is 139967911. The next prime is 139967941. The reversal of 139967939 is 939769931.

It is a strong prime.

It is an emirp because it is prime and its reverse (939769931) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 139967939 - 2¹² = 139963843 is a prime.

Together with 139967941, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (139967959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69983969 + 69983970.

It is an arithmetic number, because the mean of its divisors is an integer number (69983970).

Almost surely, 2^139967939 is an apocalyptic number.

139967939 is a deficient number, since it is larger than the sum of its proper divisors (1).

139967939 is an equidigital number, since it uses as much as digits as its factorization.

139967939 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2480058, while the sum is 56.

The square root of 139967939 is about 11830.8046640962. The cubic root of 139967939 is about 519.2097698844.

The spelling of 139967939 in words is "one hundred thirty-nine million, nine hundred sixty-seven thousand, nine hundred thirty-nine".