18816001 has 6 divisors (see below), whose sum is σ = 19670210. Its totient is φ = 17997408.

The previous prime is 18815987. The next prime is 18816019. The reversal of 18816001 is 10061881.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 18696976 + 119025 = 4324^2 + 345^2 .

It is not a de Polignac number, because 18816001 - 2⁷ = 18815873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18816601) 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, 17256 + ... + 18313.

Almost surely, 2^18816001 is an apocalyptic number.

It is an amenable number.

18816001 is a deficient number, since it is larger than the sum of its proper divisors (854209).

18816001 is an equidigital number, since it uses as much as digits as its factorization.

18816001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35615 (or 35592 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 25.

The square root of 18816001 is about 4337.7414630197. The cubic root of 18816001 is about 265.9759951579.

Adding to 18816001 its reverse (10061881), we get a palindrome (28877882).

The spelling of 18816001 in words is "eighteen million, eight hundred sixteen thousand, one".