309499940 has 12 divisors (see below), whose sum is σ = 649949916. Its totient is φ = 123799968.

The previous prime is 309499933. The next prime is 309499963. The reversal of 309499940 is 49994903.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 32809984 + 276689956 = 5728^2 + 16634^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7737479 + ... + 7737518.

It is an arithmetic number, because the mean of its divisors is an integer number (54162493).

Almost surely, 2^309499940 is an apocalyptic number.

It is an amenable number.

309499940 is an abundant number, since it is smaller than the sum of its proper divisors (340449976).

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

309499940 is a wasteful number, since it uses less digits than its factorization.

309499940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15475006 (or 15475004 counting only the distinct ones).

The product of its (nonzero) digits is 314928, while the sum is 47.

The square root of 309499940 is about 17592.6103804978. The cubic root of 309499940 is about 676.4258401357.

The spelling of 309499940 in words is "three hundred nine million, four hundred ninety-nine thousand, nine hundred forty".