19918900 has 36 divisors (see below), whose sum is σ = 45770508. Its totient is φ = 7498240.

The previous prime is 19918753. The next prime is 19918901. The reversal of 19918900 is 981991.

It can be written as a sum of positive squares in 6 ways, for example, as 2396304 + 17522596 = 1548^2 + 4186^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 19918900.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19918901) 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 in 11 ways as a sum of consecutive naturals, for example, 4159 + ... + 7558.

It is an arithmetic number, because the mean of its divisors is an integer number (1271403).

Almost surely, 2^19918900 is an apocalyptic number.

19918900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19918900 is an abundant number, since it is smaller than the sum of its proper divisors (25851608).

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

19918900 is a wasteful number, since it uses less digits than its factorization.

19918900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11748 (or 11741 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 37.

The square root of 19918900 is about 4463.0594887364. The cubic root of 19918900 is about 271.0743658332.

The spelling of 19918900 in words is "nineteen million, nine hundred eighteen thousand, nine hundred".