309730 has 16 divisors (see below), whose sum is σ = 570240. Its totient is φ = 121072.

The previous prime is 309713. The next prime is 309731. The reversal of 309730 is 37903.

It is not an unprimeable number, because it can be changed into a prime (309731) by changing a digit.

309730 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 141 + ... + 799.

It is an arithmetic number, because the mean of its divisors is an integer number (35640).

2³⁰⁹⁷³⁰ is an apocalyptic number.

309730 is a deficient number, since it is larger than the sum of its proper divisors (260510).

309730 is a wasteful number, since it uses less digits than its factorization.

309730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 713.

The product of its (nonzero) digits is 567, while the sum is 22.

The square root of 309730 is about 556.5339163070. The cubic root of 309730 is about 67.6593400735.

The spelling of 309730 in words is "three hundred nine thousand, seven hundred thirty".