199681438 has 16 divisors (see below), whose sum is σ = 327525120. Its totient is φ = 90549400.

The previous prime is 199681403. The next prime is 199681441. The reversal of 199681438 is 834186991.

It is a junction number, because it is equal to n+sod(n) for n = 199681391 and 199681400.

It is a congruent number.

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, 1048 + ... + 20011.

It is an arithmetic number, because the mean of its divisors is an integer number (20470320).

Almost surely, 2^199681438 is an apocalyptic number.

199681438 is a deficient number, since it is larger than the sum of its proper divisors (127843682).

199681438 is a wasteful number, since it uses less digits than its factorization.

199681438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21503.

The product of its digits is 373248, while the sum is 49.

The square root of 199681438 is about 14130.8682677322. The cubic root of 199681438 is about 584.4928889978.

The spelling of 199681438 in words is "one hundred ninety-nine million, six hundred eighty-one thousand, four hundred thirty-eight".