306978997 has 4 divisors (see below), whose sum is σ = 330592780. Its totient is φ = 283365216.

The previous prime is 306978983. The next prime is 306979027. The reversal of 306978997 is 799879603.

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 34035556 + 272943441 = 5834^2 + 16521^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-306978997 is a prime.

It is a super-2 number, since 2×306978997² = 188472209198252018, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (306978967) by changing a digit.

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, 11806872 + ... + 11806897.

It is an arithmetic number, because the mean of its divisors is an integer number (82648195).

Almost surely, 2^306978997 is an apocalyptic number.

It is an amenable number.

306978997 is a deficient number, since it is larger than the sum of its proper divisors (23613783).

306978997 is a wasteful number, since it uses less digits than its factorization.

306978997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23613782.

The product of its (nonzero) digits is 5143824, while the sum is 58.

The square root of 306978997 is about 17520.8161054216. The cubic root of 306978997 is about 674.5842868709.

The spelling of 306978997 in words is "three hundred six million, nine hundred seventy-eight thousand, nine hundred ninety-seven".