199634561 has 16 divisors (see below), whose sum is σ = 230615424. Its totient is φ = 169281024.

The previous prime is 199634551. The next prime is 199634563. The reversal of 199634561 is 165436991.

199634561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 199634561 - 2²² = 195440257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (199634563) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 427250 + ... + 427716.

It is an arithmetic number, because the mean of its divisors is an integer number (14413464).

Almost surely, 2^199634561 is an apocalyptic number.

It is an amenable number.

199634561 is a deficient number, since it is larger than the sum of its proper divisors (30980863).

199634561 is a wasteful number, since it uses less digits than its factorization.

199634561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1000.

The product of its digits is 174960, while the sum is 44.

The square root of 199634561 is about 14129.2094966421. The cubic root of 199634561 is about 584.4471471105.

The spelling of 199634561 in words is "one hundred ninety-nine million, six hundred thirty-four thousand, five hundred sixty-one".