308399972 has 6 divisors (see below), whose sum is σ = 539699958. Its totient is φ = 154199984.

The previous prime is 308399969. The next prime is 308399981. The reversal of 308399972 is 279993803.

It can be written as a sum of positive squares in only one way, i.e., 189502756 + 118897216 = 13766^2 + 10904^2 .

It is a super-2 number, since 2×308399972² = 190221085459201568, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 308399972.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38549993 + ... + 38550000.

It is an arithmetic number, because the mean of its divisors is an integer number (89949993).

Almost surely, 2^308399972 is an apocalyptic number.

It is an amenable number.

308399972 is a deficient number, since it is larger than the sum of its proper divisors (231299986).

308399972 is a wasteful number, since it uses less digits than its factorization.

308399972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77099997 (or 77099995 counting only the distinct ones).

The product of its (nonzero) digits is 734832, while the sum is 50.

The square root of 308399972 is about 17561.3203376056. The cubic root of 308399972 is about 675.6235459849.

The spelling of 308399972 in words is "three hundred eight million, three hundred ninety-nine thousand, nine hundred seventy-two".