199421840 has 40 divisors (see below), whose sum is σ = 464434560. Its totient is φ = 79634816.

The previous prime is 199421837. The next prime is 199421863. The reversal of 199421840 is 48124991.

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

It is a junction number, because it is equal to n+sod(n) for n = 199421794 and 199421803.

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, 55787 + ... + 59253.

It is an arithmetic number, because the mean of its divisors is an integer number (11610864).

Almost surely, 2^199421840 is an apocalyptic number.

199421840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

199421840 is an abundant number, since it is smaller than the sum of its proper divisors (265012720).

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

199421840 is a wasteful number, since it uses less digits than its factorization.

199421840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4199 (or 4193 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 38.

The square root of 199421840 is about 14121.6797867676. The cubic root of 199421840 is about 584.2394870656.

The spelling of 199421840 in words is "one hundred ninety-nine million, four hundred twenty-one thousand, eight hundred forty".