199771920 has 100 divisors (see below), whose sum is σ = 693859980. Its totient is φ = 53270784.

The previous prime is 199771877. The next prime is 199771973. The reversal of 199771920 is 29177991.

It can be written as a sum of positive squares in 2 ways, for example, as 129413376 + 70358544 = 11376^2 + 8388^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 8935 + ... + 21894.

Almost surely, 2^199771920 is an apocalyptic number.

199771920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

199771920 is an abundant number, since it is smaller than the sum of its proper divisors (494088060).

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

199771920 is a wasteful number, since it uses less digits than its factorization.

199771920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30854 (or 30839 counting only the distinct ones).

The product of its (nonzero) digits is 71442, while the sum is 45.

The square root of 199771920 is about 14134.0694776841. The cubic root of 199771920 is about 584.5811597622.

The spelling of 199771920 in words is "one hundred ninety-nine million, seven hundred seventy-one thousand, nine hundred twenty".