72302509 has 4 divisors (see below), whose sum is σ = 74634880. Its totient is φ = 69970140.

The previous prime is 72302453. The next prime is 72302521. The reversal of 72302509 is 90520327.

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.

It is a cyclic number.

It is not a de Polignac number, because 72302509 - 2⁷ = 72302381 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 (72302569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1166139 + ... + 1166200.

It is an arithmetic number, because the mean of its divisors is an integer number (18658720).

Almost surely, 2^72302509 is an apocalyptic number.

It is an amenable number.

72302509 is a deficient number, since it is larger than the sum of its proper divisors (2332371).

72302509 is a wasteful number, since it uses less digits than its factorization.

72302509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2332370.

The product of its (nonzero) digits is 3780, while the sum is 28.

The square root of 72302509 is about 8503.0882037058. The cubic root of 72302509 is about 416.5985839338.

The spelling of 72302509 in words is "seventy-two million, three hundred two thousand, five hundred nine".