309942993 has 8 divisors (see below), whose sum is σ = 421054848. Its totient is φ = 202729904.

The previous prime is 309942977. The next prime is 309943003. The reversal of 309942993 is 399249903.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 309942993 - 2⁴ = 309942977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (309942943) 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, 974505 + ... + 974822.

It is an arithmetic number, because the mean of its divisors is an integer number (52631856).

Almost surely, 2^309942993 is an apocalyptic number.

It is an amenable number.

309942993 is a deficient number, since it is larger than the sum of its proper divisors (111111855).

309942993 is a wasteful number, since it uses less digits than its factorization.

309942993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1949383.

The product of its (nonzero) digits is 472392, while the sum is 48.

The square root of 309942993 is about 17605.1978972121. The cubic root of 309942993 is about 676.7484568993.

The spelling of 309942993 in words is "three hundred nine million, nine hundred forty-two thousand, nine hundred ninety-three".