66072309 has 8 divisors (see below), whose sum is σ = 88160352. Its totient is φ = 44016240.

The previous prime is 66072289. The next prime is 66072311. The reversal of 66072309 is 90327066.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66072309 - 2⁸ = 66072053 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66072309.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66072359) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2662 + ... + 11799.

It is an arithmetic number, because the mean of its divisors is an integer number (11020044).

Almost surely, 2^66072309 is an apocalyptic number.

It is an amenable number.

66072309 is a deficient number, since it is larger than the sum of its proper divisors (22088043).

66072309 is a wasteful number, since it uses less digits than its factorization.

66072309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15987.

The product of its (nonzero) digits is 13608, while the sum is 33.

The square root of 66072309 is about 8128.4874976837. The cubic root of 66072309 is about 404.2715330584.

The spelling of 66072309 in words is "sixty-six million, seventy-two thousand, three hundred nine".