71839909 has 12 divisors (see below), whose sum is σ = 76646848. Its totient is φ = 67320000.

The previous prime is 71839897. The next prime is 71839921. The reversal of 71839909 is 90993817.

It is an interprime number because it is at equal distance from previous prime (71839897) and next prime (71839921).

It is not a de Polignac number, because 71839909 - 2⁵ = 71839877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71839939) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 95284 + ... + 96034.

Almost surely, 2^71839909 is an apocalyptic number.

It is an amenable number.

71839909 is a deficient number, since it is larger than the sum of its proper divisors (4806939).

71839909 is a wasteful number, since it uses less digits than its factorization.

71839909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1116 (or 1099 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 46.

The square root of 71839909 is about 8475.8426719707. The cubic root of 71839909 is about 415.7081999682.

The spelling of 71839909 in words is "seventy-one million, eight hundred thirty-nine thousand, nine hundred nine".