199664640 has 264 divisors, whose sum is σ = 791943360. Its totient is φ = 45563904.

The previous prime is 199664639. The next prime is 199664653. The reversal of 199664640 is 46466991.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 322251 + ... + 322869.

Almost surely, 2^199664640 is an apocalyptic number.

199664640 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 199664640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (395971680).

199664640 is an abundant number, since it is smaller than the sum of its proper divisors (592278720).

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

199664640 is a wasteful number, since it uses less digits than its factorization.

199664640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 657 (or 636 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 45.

The square root of 199664640 is about 14130.2738826960. The cubic root of 199664640 is about 584.4764985795.

The spelling of 199664640 in words is "one hundred ninety-nine million, six hundred sixty-four thousand, six hundred forty".