21795953 has 4 divisors (see below), whose sum is σ = 21814128. Its totient is φ = 21777780.

The previous prime is 21795947. The next prime is 21795959. The reversal of 21795953 is 35959712.

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 an interprime number because it is at equal distance from previous prime (21795947) and next prime (21795959).

It is a cyclic number.

It is not a de Polignac number, because 21795953 - 2¹⁶ = 21730417 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21795953.

It is not an unprimeable number, because it can be changed into a prime (21795959) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7151 + ... + 9732.

It is an arithmetic number, because the mean of its divisors is an integer number (5453532).

Almost surely, 2^21795953 is an apocalyptic number.

It is an amenable number.

21795953 is a deficient number, since it is larger than the sum of its proper divisors (18175).

21795953 is a wasteful number, since it uses less digits than its factorization.

21795953 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18174.

The product of its digits is 85050, while the sum is 41.

The square root of 21795953 is about 4668.6136057721. The cubic root of 21795953 is about 279.3349565331.

The spelling of 21795953 in words is "twenty-one million, seven hundred ninety-five thousand, nine hundred fifty-three".