199665900 has 216 divisors, whose sum is σ = 733640544. Its totient is φ = 44467200.

The previous prime is 199665883. The next prime is 199665911. The reversal of 199665900 is 9566991.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 257914 + ... + 258686.

It is an arithmetic number, because the mean of its divisors is an integer number (3396484).

Almost surely, 2^199665900 is an apocalyptic number.

199665900 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 199665900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (366820272).

199665900 is an abundant number, since it is smaller than the sum of its proper divisors (533974644).

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

199665900 is a wasteful number, since it uses less digits than its factorization.

199665900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 841 (or 831 counting only the distinct ones).

The product of its (nonzero) digits is 131220, while the sum is 45.

The square root of 199665900 is about 14130.3184677487. The cubic root of 199665900 is about 584.4777280392.

It can be divided in two parts, 1996 and 65900, that added together give a triangular number (67896 = T₃₆₈).

The spelling of 199665900 in words is "one hundred ninety-nine million, six hundred sixty-five thousand, nine hundred".