181940400 has 90 divisors (see below), whose sum is σ = 631396220. Its totient is φ = 48516480.

The previous prime is 181940389. The next prime is 181940413. The reversal of 181940400 is 4049181.

It is a tau number, because it is divible by the number of its divisors (90).

It is an unprimeable number.

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 17 ways as a sum of consecutive naturals, for example, 21670 + ... + 28869.

Almost surely, 2^181940400 is an apocalyptic number.

181940400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

181940400 is an abundant number, since it is smaller than the sum of its proper divisors (449455820).

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

181940400 is a wasteful number, since it uses less digits than its factorization.

181940400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50563 (or 50549 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 181940400 is about 13488.5284593984. The cubic root of 181940400 is about 566.6432439377.

Adding to 181940400 its reverse (4049181), we get a palindrome (185989581).

The spelling of 181940400 in words is "one hundred eighty-one million, nine hundred forty thousand, four hundred".