18931400 has 48 divisors (see below), whose sum is σ = 44491200. Its totient is φ = 7490880.

The previous prime is 18931399. The next prime is 18931417. The reversal of 18931400 is 413981.

It is a self number, because there is not a number n which added to its sum of digits gives 18931400.

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 11 ways as a sum of consecutive naturals, for example, 20141 + ... + 21059.

It is an arithmetic number, because the mean of its divisors is an integer number (926900).

Almost surely, 2^18931400 is an apocalyptic number.

18931400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18931400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22245600).

18931400 is an abundant number, since it is smaller than the sum of its proper divisors (25559800).

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

18931400 is a wasteful number, since it uses less digits than its factorization.

18931400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1038 (or 1029 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 18931400 is about 4351.0228682460. The cubic root of 18931400 is about 266.5186331157.

The spelling of 18931400 in words is "eighteen million, nine hundred thirty-one thousand, four hundred".