199995905 has 16 divisors (see below), whose sum is σ = 256977360. Its totient is φ = 148887552.

The previous prime is 199995889. The next prime is 199995923. The reversal of 199995905 is 509599991.

199995905 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 1721344 + 198274561 = 1312^2 + 14081^2 .

It is a cyclic number.

It is not a de Polignac number, because 199995905 - 2⁴ = 199995889 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5654 + ... + 20783.

It is an arithmetic number, because the mean of its divisors is an integer number (16061085).

Almost surely, 2^199995905 is an apocalyptic number.

It is an amenable number.

199995905 is a deficient number, since it is larger than the sum of its proper divisors (56981455).

199995905 is a wasteful number, since it uses less digits than its factorization.

199995905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26548.

The product of its (nonzero) digits is 1476225, while the sum is 56.

The square root of 199995905 is about 14141.9908428764. The cubic root of 199995905 is about 584.7995563311.

The spelling of 199995905 in words is "one hundred ninety-nine million, nine hundred ninety-five thousand, nine hundred five".