199668174640 has 40 divisors (see below), whose sum is σ = 506431099728. Its totient is φ = 72606608640.

The previous prime is 199668174623. The next prime is 199668174653. The reversal of 199668174640 is 46471866991.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Smith number, since the sum of its digits (61) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 113446947 + ... + 113448706.

Almost surely, 2^199668174640 is an apocalyptic number.

199668174640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

199668174640 is an abundant number, since it is smaller than the sum of its proper divisors (306762925088).

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

199668174640 is a wasteful number, since it uses less digits than its factorization.

199668174640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226895677 (or 226895671 counting only the distinct ones).

The product of its (nonzero) digits is 15676416, while the sum is 61.

The spelling of 199668174640 in words is "one hundred ninety-nine billion, six hundred sixty-eight million, one hundred seventy-four thousand, six hundred forty".