71721324 has 18 divisors (see below), whose sum is σ = 181295660. Its totient is φ = 23907096.

The previous prime is 71721319. The next prime is 71721343. The reversal of 71721324 is 42312717.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (18).

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 996094 + ... + 996165.

Almost surely, 2^71721324 is an apocalyptic number.

It is an amenable number.

71721324 is an abundant number, since it is smaller than the sum of its proper divisors (109574336).

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

71721324 is a wasteful number, since it uses less digits than its factorization.

71721324 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1992269 (or 1992264 counting only the distinct ones).

The product of its digits is 2352, while the sum is 27.

The square root of 71721324 is about 8468.8443131280. The cubic root of 71721324 is about 415.4793396826.

The spelling of 71721324 in words is "seventy-one million, seven hundred twenty-one thousand, three hundred twenty-four".