306981 has 12 divisors (see below), whose sum is σ = 463008. Its totient is φ = 195624.

The previous prime is 306953. The next prime is 306991. The reversal of 306981 is 189603.

It is not a de Polignac number, because 306981 - 2⁵ = 306949 is a prime.

It is a super-2 number, since 2×306981² = 188474668722, which contains 22 as substring.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is an Ulam number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 306981.

It is not an unprimeable number, because it can be changed into a prime (306941) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 535 + ... + 948.

It is an arithmetic number, because the mean of its divisors is an integer number (38584).

2³⁰⁶⁹⁸¹ is an apocalyptic number.

It is an amenable number.

306981 is a deficient number, since it is larger than the sum of its proper divisors (156027).

306981 is a wasteful number, since it uses less digits than its factorization.

306981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1512 (or 1509 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 306981 is about 554.0586611542. The cubic root of 306981 is about 67.4585754061.

The spelling of 306981 in words is "three hundred six thousand, nine hundred eighty-one".