72309005 has 4 divisors (see below), whose sum is σ = 86770812. Its totient is φ = 57847200.

The previous prime is 72309001. The next prime is 72309023. The reversal of 72309005 is 50090327.

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 38180041 + 34128964 = 6179^2 + 5842^2 .

It is not a de Polignac number, because 72309005 - 2² = 72309001 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72309001) 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, 7230896 + ... + 7230905.

It is an arithmetic number, because the mean of its divisors is an integer number (21692703).

Almost surely, 2^72309005 is an apocalyptic number.

It is an amenable number.

72309005 is a deficient number, since it is larger than the sum of its proper divisors (14461807).

72309005 is a wasteful number, since it uses less digits than its factorization.

72309005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14461806.

The product of its (nonzero) digits is 1890, while the sum is 26.

The square root of 72309005 is about 8503.4701739937. The cubic root of 72309005 is about 416.6110599571.

The spelling of 72309005 in words is "seventy-two million, three hundred nine thousand, five".