72038009 has 4 divisors (see below), whose sum is σ = 72198900. Its totient is φ = 71877120.

The previous prime is 72037969. The next prime is 72038051. The reversal of 72038009 is 90083027.

72038009 = 155² + 156² + ... + 603².

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 61669609 + 10368400 = 7853^2 + 3220^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72038009 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (72038069) 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, 79772 + ... + 80669.

It is an arithmetic number, because the mean of its divisors is an integer number (18049725).

Almost surely, 2^72038009 is an apocalyptic number.

It is an amenable number.

72038009 is a deficient number, since it is larger than the sum of its proper divisors (160891).

72038009 is a wasteful number, since it uses less digits than its factorization.

72038009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160890.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 72038009 is about 8487.5207805342. The cubic root of 72038009 is about 416.0899572009.

The spelling of 72038009 in words is "seventy-two million, thirty-eight thousand, nine".