199681610 has 16 divisors (see below), whose sum is σ = 362052936. Its totient is φ = 79289088.

The previous prime is 199681589. The next prime is 199681619. The reversal of 199681610 is 16186991.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 161772961 + 37908649 = 12719^2 + 6157^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (199681619) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 71507 + ... + 74246.

Almost surely, 2^199681610 is an apocalyptic number.

199681610 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

199681610 is a deficient number, since it is larger than the sum of its proper divisors (162371326).

199681610 is a wasteful number, since it uses less digits than its factorization.

199681610 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145897.

The product of its (nonzero) digits is 23328, while the sum is 41.

The square root of 199681610 is about 14130.8743536980. The cubic root of 199681610 is about 584.4930568197.

The spelling of 199681610 in words is "one hundred ninety-nine million, six hundred eighty-one thousand, six hundred ten".