71209128 has 32 divisors (see below), whose sum is σ = 182367360. Its totient is φ = 23157120.

The previous prime is 71209121. The next prime is 71209129. The reversal of 71209128 is 82190217.

It is a junction number, because it is equal to n+sod(n) for n = 71209095 and 71209104.

It is not an unprimeable number, because it can be changed into a prime (71209121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35200 + ... + 37167.

It is an arithmetic number, because the mean of its divisors is an integer number (5698980).

Almost surely, 2^71209128 is an apocalyptic number.

It is an amenable number.

71209128 is an abundant number, since it is smaller than the sum of its proper divisors (111158232).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

71209128 is a wasteful number, since it uses less digits than its factorization.

71209128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72417 (or 72413 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 30.

The square root of 71209128 is about 8438.5501124305. The cubic root of 71209128 is about 414.4879308595.

The spelling of 71209128 in words is "seventy-one million, two hundred nine thousand, one hundred twenty-eight".