305906 has 4 divisors (see below), whose sum is σ = 458862. Its totient is φ = 152952.

The previous prime is 305873. The next prime is 305917. The reversal of 305906 is 609503.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 292681 + 13225 = 541^2 + 115^2 .

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 305906.

It is an unprimeable number.

305906 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 as a sum of consecutive naturals, namely, 76475 + ... + 76478.

2³⁰⁵⁹⁰⁶ is an apocalyptic number.

305906 is a deficient number, since it is larger than the sum of its proper divisors (152956).

305906 is a wasteful number, since it uses less digits than its factorization.

305906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152955.

The product of its (nonzero) digits is 810, while the sum is 23.

The square root of 305906 is about 553.0876964822. The cubic root of 305906 is about 67.3797401442.

The spelling of 305906 in words is "three hundred five thousand, nine hundred six".