18380146 has 4 divisors (see below), whose sum is σ = 27570222. Its totient is φ = 9190072.

The previous prime is 18380143. The next prime is 18380189. The reversal of 18380146 is 64108381.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 64108381 = 73 ⋅878197.

It can be written as a sum of positive squares in only one way, i.e., 13140625 + 5239521 = 3625^2 + 2289^2 .

It is a Smith number, since the sum of its digits (31) 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 (18380143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4595035 + ... + 4595038.

Almost surely, 2^18380146 is an apocalyptic number.

18380146 is a deficient number, since it is larger than the sum of its proper divisors (9190076).

18380146 is an equidigital number, since it uses as much as digits as its factorization.

18380146 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9190075.

The product of its (nonzero) digits is 4608, while the sum is 31.

The square root of 18380146 is about 4287.2072494807. The cubic root of 18380146 is about 263.9062358327.

The spelling of 18380146 in words is "eighteen million, three hundred eighty thousand, one hundred forty-six".