72127709 has 4 divisors (see below), whose sum is σ = 72316416. Its totient is φ = 71939004.

The previous prime is 72127673. The next prime is 72127721. The reversal of 72127709 is 90772127.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 90772127 = 131 ⋅692917.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72127709 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 (72127799) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 93779 + ... + 94544.

It is an arithmetic number, because the mean of its divisors is an integer number (18079104).

Almost surely, 2^72127709 is an apocalyptic number.

It is an amenable number.

72127709 is a deficient number, since it is larger than the sum of its proper divisors (188707).

72127709 is a wasteful number, since it uses less digits than its factorization.

72127709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188706.

The product of its (nonzero) digits is 12348, while the sum is 35.

The square root of 72127709 is about 8492.8033652028. The cubic root of 72127709 is about 416.2625873122.

The spelling of 72127709 in words is "seventy-two million, one hundred twenty-seven thousand, seven hundred nine".