18208413 has 6 divisors (see below), whose sum is σ = 26301054. Its totient is φ = 12138936.

The previous prime is 18208409. The next prime is 18208451. The reversal of 18208413 is 31480281.

It can be written as a sum of positive squares in only one way, i.e., 16867449 + 1340964 = 4107^2 + 1158^2 .

It is not a de Polignac number, because 18208413 - 2² = 18208409 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18208493) 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, 1011570 + ... + 1011587.

It is an arithmetic number, because the mean of its divisors is an integer number (4383509).

Almost surely, 2^18208413 is an apocalyptic number.

It is an amenable number.

18208413 is a deficient number, since it is larger than the sum of its proper divisors (8092641).

18208413 is a wasteful number, since it uses less digits than its factorization.

18208413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2023163 (or 2023160 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 18208413 is about 4267.1317064276. The cubic root of 18208413 is about 263.0817356926.

Adding to 18208413 its reverse (31480281), we get a palindrome (49688694).

The spelling of 18208413 in words is "eighteen million, two hundred eight thousand, four hundred thirteen".