306711981 has 16 divisors (see below), whose sum is σ = 466670400. Its totient is φ = 198947664.

The previous prime is 306711973. The next prime is 306712013. The reversal of 306711981 is 189117603.

It is not a de Polignac number, because 306711981 - 2³ = 306711973 is a prime.

It is a super-2 number, since 2×306711981² = 188144478577888722, which contains 22 as substring.

It is a zygodrome in base 8.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (306711931) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 152511 + ... + 154508.

It is an arithmetic number, because the mean of its divisors is an integer number (29166900).

Almost surely, 2^306711981 is an apocalyptic number.

It is an amenable number.

306711981 is a deficient number, since it is larger than the sum of its proper divisors (159958419).

306711981 is a wasteful number, since it uses less digits than its factorization.

306711981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 307065 (or 307059 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 306711981 is about 17513.1944830177. The cubic root of 306711981 is about 674.3886415116.

The spelling of 306711981 in words is "three hundred six million, seven hundred eleven thousand, nine hundred eighty-one".