199864665 has 320 divisors, whose sum is σ = 526901760. Its totient is φ = 69672960.

The previous prime is 199864661. The next prime is 199864669. The reversal of 199864665 is 566468991.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (199864661) and next prime (199864669).

It is not a de Polignac number, because 199864665 - 2² = 199864661 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199864661) by changing a digit.

It is a polite number, since it can be written in 319 ways as a sum of consecutive naturals, for example, 6891871 + ... + 6891899.

It is an arithmetic number, because the mean of its divisors is an integer number (1646568).

Almost surely, 2^199864665 is an apocalyptic number.

199864665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

199864665 is an abundant number, since it is smaller than the sum of its proper divisors (327037095).

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

199864665 is a wasteful number, since it uses less digits than its factorization.

199864665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94 (or 85 counting only the distinct ones).

The product of its digits is 2799360, while the sum is 54.

The square root of 199864665 is about 14137.3499992042. The cubic root of 199864665 is about 584.6716105651.

The spelling of 199864665 in words is "one hundred ninety-nine million, eight hundred sixty-four thousand, six hundred sixty-five".