18366937 has 4 divisors (see below), whose sum is σ = 18381220. Its totient is φ = 18352656.

The previous prime is 18366923. The next prime is 18366979. The reversal of 18366937 is 73966381.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 73966381 = 443 ⋅166967.

It can be written as a sum of positive squares in 2 ways, for example, as 2653641 + 15713296 = 1629^2 + 3964^2 .

It is a 4-Lehmer number, since φ(18366937) divides (18366937-1)⁴.

It is a cyclic number.

It is not a de Polignac number, because 18366937 - 2⁷ = 18366809 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18366893 and 18366902.

It is not an unprimeable number, because it can be changed into a prime (18366437) 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, 4998 + ... + 7855.

It is an arithmetic number, because the mean of its divisors is an integer number (4595305).

It is a Poulet number, since it divides 2^18366936-1.

Almost surely, 2^18366937 is an apocalyptic number.

It is an amenable number.

18366937 is a deficient number, since it is larger than the sum of its proper divisors (14283).

18366937 is a wasteful number, since it uses less digits than its factorization.

18366937 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14282.

The product of its digits is 163296, while the sum is 43.

The square root of 18366937 is about 4285.6664592569. Note that the first 3 decimals coincide. The cubic root of 18366937 is about 263.8430014263.

The spelling of 18366937 in words is "eighteen million, three hundred sixty-six thousand, nine hundred thirty-seven".