199780 has 24 divisors (see below), whose sum is σ = 479808. Its totient is φ = 68448.

The previous prime is 199777. The next prime is 199783. The reversal of 199780 is 87991.

199780 = 30² + 31² + ... + 85².

It is an interprime number because it is at equal distance from previous prime (199777) and next prime (199783).

It is a nialpdrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (199783) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 574 + ... + 853.

It is an arithmetic number, because the mean of its divisors is an integer number (19992).

2¹⁹⁹⁷⁸⁰ is an apocalyptic number.

199780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

199780 is an abundant number, since it is smaller than the sum of its proper divisors (280028).

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

199780 is a wasteful number, since it uses less digits than its factorization.

199780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1443 (or 1441 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 34.

The square root of 199780 is about 446.9675603441. The cubic root of 199780 is about 58.4589041003.

It can be divided in two parts, 199 and 780, that added together give a palindrome (979).

The spelling of 199780 in words is "one hundred ninety-nine thousand, seven hundred eighty".