18195400 has 24 divisors (see below), whose sum is σ = 42304770. Its totient is φ = 7278080.

The previous prime is 18195361. The next prime is 18195409. The reversal of 18195400 is 459181.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 8868484 + 9326916 = 2978^2 + 3054^2 .

It is not an unprimeable number, because it can be changed into a prime (18195409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 45289 + ... + 45688.

Almost surely, 2^18195400 is an apocalyptic number.

18195400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18195400 is an abundant number, since it is smaller than the sum of its proper divisors (24109370).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18195400 is a wasteful number, since it uses less digits than its factorization.

18195400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90993 (or 90984 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 18195400 is about 4265.6066391546. The cubic root of 18195400 is about 263.0190485801.

The spelling of 18195400 in words is "eighteen million, one hundred ninety-five thousand, four hundred".