199988406 has 64 divisors (see below), whose sum is σ = 463276800. Its totient is φ = 63892800.

The previous prime is 199988387. The next prime is 199988413. The reversal of 199988406 is 604889991.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 129861 + ... + 131391.

It is an arithmetic number, because the mean of its divisors is an integer number (7238700).

Almost surely, 2^199988406 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 199988406, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (231638400).

199988406 is an abundant number, since it is smaller than the sum of its proper divisors (263288394).

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

199988406 is a wasteful number, since it uses less digits than its factorization.

199988406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1642 (or 1636 counting only the distinct ones).

The product of its (nonzero) digits is 1119744, while the sum is 54.

The square root of 199988406 is about 14141.7257079891. The cubic root of 199988406 is about 584.7922470703.

The spelling of 199988406 in words is "one hundred ninety-nine million, nine hundred eighty-eight thousand, four hundred six".