71839939 has 2 divisors, whose sum is σ = 71839940. Its totient is φ = 71839938.

The previous prime is 71839921. The next prime is 71839949. The reversal of 71839939 is 93993817.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71839939 is a prime.

It is a super-3 number, since 3×71839939³ (a number of 25 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 71839892 and 71839901.

It is not a weakly prime, because it can be changed into another prime (71839949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35919969 + 35919970.

It is an arithmetic number, because the mean of its divisors is an integer number (35919970).

Almost surely, 2^71839939 is an apocalyptic number.

71839939 is a deficient number, since it is larger than the sum of its proper divisors (1).

71839939 is an equidigital number, since it uses as much as digits as its factorization.

71839939 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 367416, while the sum is 49.

The square root of 71839939 is about 8475.8444417061. The cubic root of 71839939 is about 415.7082578341.

The spelling of 71839939 in words is "seventy-one million, eight hundred thirty-nine thousand, nine hundred thirty-nine".