72301309 has 4 divisors (see below), whose sum is σ = 72318400. Its totient is φ = 72284220.

The previous prime is 72301301. The next prime is 72301337. The reversal of 72301309 is 90310327.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 72301309 - 2³ = 72301301 is a prime.

It is a super-2 number, since 2×72301309² = 10454958566226962, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72301301) 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, 3004 + ... + 12394.

It is an arithmetic number, because the mean of its divisors is an integer number (18079600).

Almost surely, 2^72301309 is an apocalyptic number.

It is an amenable number.

72301309 is a deficient number, since it is larger than the sum of its proper divisors (17091).

72301309 is an equidigital number, since it uses as much as digits as its factorization.

72301309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17090.

The product of its (nonzero) digits is 1134, while the sum is 25.

The square root of 72301309 is about 8503.0176408143. The cubic root of 72301309 is about 416.5962791679.

The spelling of 72301309 in words is "seventy-two million, three hundred one thousand, three hundred nine".