71471809 has 4 divisors (see below), whose sum is σ = 72643540. Its totient is φ = 70300080.

The previous prime is 71471801. The next prime is 71471839. The reversal of 71471809 is 90817417.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90817417 = 17 ⋅5342201.

It can be written as a sum of positive squares in 2 ways, for example, as 24850225 + 46621584 = 4985^2 + 6828^2 .

It is a cyclic number.

It is not a de Polignac number, because 71471809 - 2³ = 71471801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71471801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 585774 + ... + 585895.

It is an arithmetic number, because the mean of its divisors is an integer number (18160885).

Almost surely, 2^71471809 is an apocalyptic number.

It is an amenable number.

71471809 is a deficient number, since it is larger than the sum of its proper divisors (1171731).

71471809 is a wasteful number, since it uses less digits than its factorization.

71471809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1171730.

The product of its (nonzero) digits is 14112, while the sum is 37.

The square root of 71471809 is about 8454.1001295230. The cubic root of 71471809 is about 414.9969690590.

The spelling of 71471809 in words is "seventy-one million, four hundred seventy-one thousand, eight hundred nine".