308218518947 has 4 divisors (see below), whose sum is σ = 324440546280. Its totient is φ = 291996491616.

The previous prime is 308218518943. The next prime is 308218518953. The reversal of 308218518947 is 749815812803.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 308218518947 - 2² = 308218518943 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 308218518892 and 308218518901.

It is not an unprimeable number, because it can be changed into a prime (308218518943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8111013638 + ... + 8111013675.

It is an arithmetic number, because the mean of its divisors is an integer number (81110136570).

Almost surely, 2^308218518947 is an apocalyptic number.

308218518947 is a deficient number, since it is larger than the sum of its proper divisors (16222027333).

308218518947 is a wasteful number, since it uses less digits than its factorization.

308218518947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16222027332.

The product of its (nonzero) digits is 3870720, while the sum is 56.

The spelling of 308218518947 in words is "three hundred eight billion, two hundred eighteen million, five hundred eighteen thousand, nine hundred forty-seven".