20818233 has 6 divisors (see below), whose sum is σ = 30070794. Its totient is φ = 13878816.

The previous prime is 20818229. The next prime is 20818247. The reversal of 20818233 is 33281802.

It can be written as a sum of positive squares in only one way, i.e., 20766249 + 51984 = 4557^2 + 228^2 .

It is not a de Polignac number, because 20818233 - 2² = 20818229 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20818197 and 20818206.

It is not an unprimeable number, because it can be changed into a prime (20818223) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1156560 + ... + 1156577.

It is an arithmetic number, because the mean of its divisors is an integer number (5011799).

Almost surely, 2^20818233 is an apocalyptic number.

It is an amenable number.

20818233 is a deficient number, since it is larger than the sum of its proper divisors (9252561).

20818233 is a wasteful number, since it uses less digits than its factorization.

20818233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2313143 (or 2313140 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 20818233 is about 4562.7001873890. The cubic root of 20818233 is about 275.0941077366.

The spelling of 20818233 in words is "twenty million, eight hundred eighteen thousand, two hundred thirty-three".