21641753 has 8 divisors (see below), whose sum is σ = 24915072. Its totient is φ = 18413856.

The previous prime is 21641747. The next prime is 21641783. The reversal of 21641753 is 35714612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21641753 - 2¹² = 21637657 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21641783) 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 7 ways as a sum of consecutive naturals, for example, 10325 + ... + 12242.

It is an arithmetic number, because the mean of its divisors is an integer number (3114384).

Almost surely, 2^21641753 is an apocalyptic number.

It is an amenable number.

21641753 is a deficient number, since it is larger than the sum of its proper divisors (3273319).

21641753 is a wasteful number, since it uses less digits than its factorization.

21641753 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22711.

The product of its digits is 5040, while the sum is 29.

The square root of 21641753 is about 4652.0697544211. The cubic root of 21641753 is about 278.6746592019.

The spelling of 21641753 in words is "twenty-one million, six hundred forty-one thousand, seven hundred fifty-three".