305998 has 16 divisors (see below), whose sum is σ = 572544. Its totient is φ = 119160.

The previous prime is 305971. The next prime is 305999. The reversal of 305998 is 899503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (305999) by changing a digit.

305998 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 840 + ... + 1147.

It is an arithmetic number, because the mean of its divisors is an integer number (35784).

2³⁰⁵⁹⁹⁸ is an apocalyptic number.

305998 is a deficient number, since it is larger than the sum of its proper divisors (266546).

305998 is a wasteful number, since it uses less digits than its factorization.

305998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2007.

The product of its (nonzero) digits is 9720, while the sum is 34.

The square root of 305998 is about 553.1708596808. The cubic root of 305998 is about 67.3864941959.

Subtracting 305998 from its reverse (899503), we obtain a triangular number (593505 = T₁₀₈₉).

The spelling of 305998 in words is "three hundred five thousand, nine hundred ninety-eight".