101905 has 8 divisors (see below), whose sum is σ = 124200. Its totient is φ = 80256.

The previous prime is 101891. The next prime is 101917. The reversal of 101905 is 509101.

It can be written as a sum of positive squares in 4 ways, for example, as 16641 + 85264 = 129^2 + 292^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 101905 - 2⁵ = 101873 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 331 + ... + 559.

It is an arithmetic number, because the mean of its divisors is an integer number (15525).

2¹⁰¹⁹⁰⁵ is an apocalyptic number.

It is an amenable number.

101905 is a deficient number, since it is larger than the sum of its proper divisors (22295).

101905 is an equidigital number, since it uses as much as digits as its factorization.

101905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323.

The product of its (nonzero) digits is 45, while the sum is 16.

The square root of 101905 is about 319.2256255378. The cubic root of 101905 is about 46.7087771821.

The spelling of 101905 in words is "one hundred one thousand, nine hundred five".