71340721 has 4 divisors (see below), whose sum is σ = 75537252. Its totient is φ = 67144192.

The previous prime is 71340701. The next prime is 71340727. The reversal of 71340721 is 12704317.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 66341025 + 4999696 = 8145^2 + 2236^2 .

It is a cyclic number.

It is not a de Polignac number, because 71340721 - 2⁷ = 71340593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71340727) 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, 2098240 + ... + 2098273.

It is an arithmetic number, because the mean of its divisors is an integer number (18884313).

Almost surely, 2^71340721 is an apocalyptic number.

It is an amenable number.

71340721 is a deficient number, since it is larger than the sum of its proper divisors (4196531).

71340721 is a wasteful number, since it uses less digits than its factorization.

71340721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4196530.

The product of its (nonzero) digits is 1176, while the sum is 25.

The square root of 71340721 is about 8446.3436468095. The cubic root of 71340721 is about 414.7430954604.

The spelling of 71340721 in words is "seventy-one million, three hundred forty thousand, seven hundred twenty-one".