21193853 has 2 divisors, whose sum is σ = 21193854. Its totient is φ = 21193852.

The previous prime is 21193847. The next prime is 21193889. The reversal of 21193853 is 35839112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15225604 + 5968249 = 3902^2 + 2443^2 .

It is a cyclic number.

It is not a de Polignac number, because 21193853 - 2⁶ = 21193789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21193813) 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 as a sum of consecutive naturals, namely, 10596926 + 10596927.

It is an arithmetic number, because the mean of its divisors is an integer number (10596927).

Almost surely, 2^21193853 is an apocalyptic number.

It is an amenable number.

21193853 is a deficient number, since it is larger than the sum of its proper divisors (1).

21193853 is an equidigital number, since it uses as much as digits as its factorization.

21193853 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6480, while the sum is 32.

The square root of 21193853 is about 4603.6782033500. The cubic root of 21193853 is about 276.7387484964.

The spelling of 21193853 in words is "twenty-one million, one hundred ninety-three thousand, eight hundred fifty-three".