309729216 has 28 divisors (see below), whose sum is σ = 819492392. Its totient is φ = 103243008.

The previous prime is 309729197. The next prime is 309729223. The reversal of 309729216 is 612927903.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 806395 + ... + 806778.

Almost surely, 2^309729216 is an apocalyptic number.

It is an amenable number.

309729216 is an abundant number, since it is smaller than the sum of its proper divisors (509763176).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

309729216 is a wasteful number, since it uses less digits than its factorization.

309729216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1613188 (or 1613178 counting only the distinct ones).

The product of its (nonzero) digits is 40824, while the sum is 39.

The square root of 309729216 is about 17599.1254328163. The cubic root of 309729216 is about 676.5928298617.

The spelling of 309729216 in words is "three hundred nine million, seven hundred twenty-nine thousand, two hundred sixteen".