20965853 has 4 divisors (see below), whose sum is σ = 21041820. Its totient is φ = 20889888.

The previous prime is 20965849. The next prime is 20965891. The reversal of 20965853 is 35856902.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 35856902 = 2 ⋅17928451.

It can be written as a sum of positive squares in 2 ways, for example, as 14273284 + 6692569 = 3778^2 + 2587^2 .

It is a cyclic number.

It is not a de Polignac number, because 20965853 - 2² = 20965849 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20965843) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37568 + ... + 38121.

It is an arithmetic number, because the mean of its divisors is an integer number (5260455).

Almost surely, 2^20965853 is an apocalyptic number.

It is an amenable number.

20965853 is a deficient number, since it is larger than the sum of its proper divisors (75967).

20965853 is an equidigital number, since it uses as much as digits as its factorization.

20965853 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75966.

The product of its (nonzero) digits is 64800, while the sum is 38.

The square root of 20965853 is about 4578.8484360153. The cubic root of 20965853 is about 275.7427984432.

The spelling of 20965853 in words is "twenty million, nine hundred sixty-five thousand, eight hundred fifty-three".