199640736 has 72 divisors (see below), whose sum is σ = 592431840. Its totient is φ = 63651456.

The previous prime is 199640731. The next prime is 199640737. The reversal of 199640736 is 637046991.

It is a tau number, because it is divible by the number of its divisors (72).

It is a junction number, because it is equal to n+sod(n) for n = 199640691 and 199640700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199640731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8446 + ... + 21693.

It is an arithmetic number, because the mean of its divisors is an integer number (8228220).

Almost surely, 2^199640736 is an apocalyptic number.

199640736 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

199640736 is an abundant number, since it is smaller than the sum of its proper divisors (392791104).

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

199640736 is a wasteful number, since it uses less digits than its factorization.

199640736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30178 (or 30167 counting only the distinct ones).

The product of its (nonzero) digits is 244944, while the sum is 45.

The square root of 199640736 is about 14129.4280139006. The cubic root of 199640736 is about 584.4531729942.

The spelling of 199640736 in words is "one hundred ninety-nine million, six hundred forty thousand, seven hundred thirty-six".