306506321 has 4 divisors (see below), whose sum is σ = 334370544. Its totient is φ = 278642100.

The previous prime is 306506297. The next prime is 306506339. The reversal of 306506321 is 123605603.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 306506321 - 2¹⁸ = 306244177 is a prime.

It is a super-2 number, since 2×306506321² = 187892249625910082, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (306506351) 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, 13932095 + ... + 13932116.

It is an arithmetic number, because the mean of its divisors is an integer number (83592636).

Almost surely, 2^306506321 is an apocalyptic number.

It is an amenable number.

306506321 is a deficient number, since it is larger than the sum of its proper divisors (27864223).

306506321 is a wasteful number, since it uses less digits than its factorization.

306506321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27864222.

The product of its (nonzero) digits is 3240, while the sum is 26.

The square root of 306506321 is about 17507.3219254117. The cubic root of 306506321 is about 674.2378748989.

The spelling of 306506321 in words is "three hundred six million, five hundred six thousand, three hundred twenty-one".