199999400 has 48 divisors (see below), whose sum is σ = 465965340. Its totient is φ = 79833600.

The previous prime is 199999391. The next prime is 199999409. The reversal of 199999400 is 4999991.

It is an interprime number because it is at equal distance from previous prime (199999391) and next prime (199999409).

It can be written as a sum of positive squares in 6 ways, for example, as 133772356 + 66227044 = 11566^2 + 8138^2 .

It is a Harshad number since it is a multiple of its sum of digits (50).

It is not an unprimeable number, because it can be changed into a prime (199999409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 150740 + ... + 152060.

Almost surely, 2^199999400 is an apocalyptic number.

199999400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

199999400 is an abundant number, since it is smaller than the sum of its proper divisors (265965940).

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

199999400 is a wasteful number, since it uses less digits than its factorization.

199999400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2094 (or 2085 counting only the distinct ones).

The product of its (nonzero) digits is 236196, while the sum is 50.

The square root of 199999400 is about 14142.1144105116. The cubic root of 199999400 is about 584.8029628384.

The spelling of 199999400 in words is "one hundred ninety-nine million, nine hundred ninety-nine thousand, four hundred".