308940508021 has 4 divisors (see below), whose sum is σ = 308945882700. Its totient is φ = 308935133344.

The previous prime is 308940507973. The next prime is 308940508039. The reversal of 308940508021 is 120805049803.

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

It can be written as a sum of positive squares in 2 ways, for example, as 198657404100 + 110283103921 = 445710^2 + 332089^2 .

It is a cyclic number.

It is not a de Polignac number, because 308940508021 - 2¹⁵ = 308940475253 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (308940508081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2600176 + ... + 2716393.

It is an arithmetic number, because the mean of its divisors is an integer number (77236470675).

Almost surely, 2^308940508021 is an apocalyptic number.

It is an amenable number.

308940508021 is a deficient number, since it is larger than the sum of its proper divisors (5374679).

308940508021 is an equidigital number, since it uses as much as digits as its factorization.

308940508021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5374678.

The product of its (nonzero) digits is 69120, while the sum is 40.

The spelling of 308940508021 in words is "three hundred eight billion, nine hundred forty million, five hundred eight thousand, twenty-one".