18340402 has 4 divisors (see below), whose sum is σ = 27510606. Its totient is φ = 9170200.

The previous prime is 18340397. The next prime is 18340409. The reversal of 18340402 is 20404381.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 15139881 + 3200521 = 3891^2 + 1789^2 .

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (18340409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4585099 + ... + 4585102.

Almost surely, 2^18340402 is an apocalyptic number.

18340402 is a deficient number, since it is larger than the sum of its proper divisors (9170204).

18340402 is an equidigital number, since it uses as much as digits as its factorization.

18340402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9170203.

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 18340402 is about 4282.5695557691. The cubic root of 18340402 is about 263.7158808242.

Adding to 18340402 its reverse (20404381), we get a palindrome (38744783).

The spelling of 18340402 in words is "eighteen million, three hundred forty thousand, four hundred two".