21195193 has 4 divisors (see below), whose sum is σ = 21279888. Its totient is φ = 21110500.

The previous prime is 21195169. The next prime is 21195197. The reversal of 21195193 is 39159112.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21195193 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21195197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41971 + ... + 42472.

It is an arithmetic number, because the mean of its divisors is an integer number (5319972).

Almost surely, 2^21195193 is an apocalyptic number.

It is an amenable number.

21195193 is a deficient number, since it is larger than the sum of its proper divisors (84695).

21195193 is an equidigital number, since it uses as much as digits as its factorization.

21195193 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84694.

The product of its digits is 2430, while the sum is 31.

The square root of 21195193 is about 4603.8237368518. The cubic root of 21195193 is about 276.7445807237.

The spelling of 21195193 in words is "twenty-one million, one hundred ninety-five thousand, one hundred ninety-three".