20641823 has 8 divisors (see below), whose sum is σ = 21546000. Its totient is φ = 19750528.

The previous prime is 20641811. The next prime is 20641837. The reversal of 20641823 is 32814602.

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 20641823 - 2¹⁴ = 20625439 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20641792 and 20641801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20641853) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 128 + ... + 6426.

It is an arithmetic number, because the mean of its divisors is an integer number (2693250).

Almost surely, 2^20641823 is an apocalyptic number.

20641823 is a deficient number, since it is larger than the sum of its proper divisors (904177).

20641823 is a wasteful number, since it uses less digits than its factorization.

20641823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6441.

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 20641823 is about 4543.3273049605. The cubic root of 20641823 is about 274.3148697022.

The spelling of 20641823 in words is "twenty million, six hundred forty-one thousand, eight hundred twenty-three".