18663413 has 4 divisors (see below), whose sum is σ = 18771468. Its totient is φ = 18555360.

The previous prime is 18663409. The next prime is 18663427. The reversal of 18663413 is 31436681.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31436681 = 569 ⋅55249.

It can be written as a sum of positive squares in 2 ways, for example, as 11303044 + 7360369 = 3362^2 + 2713^2 .

It is a cyclic number.

It is not a de Polignac number, because 18663413 - 2² = 18663409 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18663413.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18663013) 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, 53768 + ... + 54113.

It is an arithmetic number, because the mean of its divisors is an integer number (4692867).

Almost surely, 2^18663413 is an apocalyptic number.

It is an amenable number.

18663413 is a deficient number, since it is larger than the sum of its proper divisors (108055).

18663413 is a wasteful number, since it uses less digits than its factorization.

18663413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108054.

The product of its digits is 10368, while the sum is 32.

The square root of 18663413 is about 4320.1172437794. The cubic root of 18663413 is about 265.2550671001.

It can be divided in two parts, 186634 and 13, that multiplied together give a palindrome (2426242).

The spelling of 18663413 in words is "eighteen million, six hundred sixty-three thousand, four hundred thirteen".