308993 has 4 divisors (see below), whose sum is σ = 310788. Its totient is φ = 307200.

The previous prime is 308989. The next prime is 308999. The reversal of 308993 is 399803.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 399803 = 173 ⋅2311.

It can be written as a sum of positive squares in 2 ways, for example, as 223729 + 85264 = 473^2 + 292^2 .

It is a cyclic number.

It is not a de Polignac number, because 308993 - 2² = 308989 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (308999) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 608 + ... + 993.

It is an arithmetic number, because the mean of its divisors is an integer number (77697).

2³⁰⁸⁹⁹³ is an apocalyptic number.

It is an amenable number.

308993 is a deficient number, since it is larger than the sum of its proper divisors (1795).

308993 is a wasteful number, since it uses less digits than its factorization.

308993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1794.

The product of its (nonzero) digits is 5832, while the sum is 32.

The square root of 308993 is about 555.8713880027. The cubic root of 308993 is about 67.6056325034.

The spelling of 308993 in words is "three hundred eight thousand, nine hundred ninety-three".