21195 has 16 divisors (see below), whose sum is σ = 37920. Its totient is φ = 11232.

The previous prime is 21193. The next prime is 21211. The reversal of 21195 is 59112.

21195 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 21195 - 2¹ = 21193 is a prime.

It is a nialpdrome in base 13 and base 15.

It is not an unprimeable number, because it can be changed into a prime (21191) 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, 57 + ... + 213.

It is an arithmetic number, because the mean of its divisors is an integer number (2370).

2²¹¹⁹⁵ is an apocalyptic number.

21195 is a deficient number, since it is larger than the sum of its proper divisors (16725).

21195 is a wasteful number, since it uses less digits than its factorization.

21195 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171 (or 165 counting only the distinct ones).

The product of its digits is 90, while the sum is 18.

The square root of 21195 is about 145.5850267026. The cubic root of 21195 is about 27.6743740724.

It can be divided in two parts, 21 and 195, that multiplied together give a triangular number (4095 = T₉₀).

The spelling of 21195 in words is "twenty-one thousand, one hundred ninety-five".