199639440 has 480 divisors, whose sum is σ = 903442176. Its totient is φ = 38154240.

The previous prime is 199639439. The next prime is 199639459. The reversal of 199639440 is 44936991.

199639440 is a `hidden beast` number, since 1 + 9 + 9 + 639 + 4 + 4 + 0 = 666.

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 95 ways as a sum of consecutive naturals, for example, 720582 + ... + 720858.

Almost surely, 2^199639440 is an apocalyptic number.

199639440 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 199639440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (451721088).

199639440 is an abundant number, since it is smaller than the sum of its proper divisors (703802736).

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

199639440 is a wasteful number, since it uses less digits than its factorization.

199639440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 327 (or 318 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 45.

The square root of 199639440 is about 14129.3821520971. The cubic root of 199639440 is about 584.4519083008.

It can be divided in two parts, 19963 and 9440, that added together give a triangular number (29403 = T₂₄₂).

The spelling of 199639440 in words is "one hundred ninety-nine million, six hundred thirty-nine thousand, four hundred forty".