199764 has 36 divisors (see below), whose sum is σ = 524160. Its totient is φ = 64080.

The previous prime is 199753. The next prime is 199777. The reversal of 199764 is 467991.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nialpdrome in base 12.

It is a congruent number.

It is an unprimeable number.

199764 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1027 + ... + 1205.

It is an arithmetic number, because the mean of its divisors is an integer number (14560).

2¹⁹⁹⁷⁶⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 199764, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (262080).

199764 is an abundant number, since it is smaller than the sum of its proper divisors (324396).

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

199764 is a wasteful number, since it uses less digits than its factorization.

199764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220 (or 215 counting only the distinct ones).

The product of its digits is 13608, while the sum is 36.

The square root of 199764 is about 446.9496615951. The cubic root of 199764 is about 58.4573434379.

The spelling of 199764 in words is "one hundred ninety-nine thousand, seven hundred sixty-four".