20241021 has 4 divisors (see below), whose sum is σ = 26988032. Its totient is φ = 13494012.

The previous prime is 20241017. The next prime is 20241029. The reversal of 20241021 is 12014202.

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 not a de Polignac number, because 20241021 - 2² = 20241017 is a prime.

It is a super-2 number, since 2×20241021² = 819397862244882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20240988 and 20241006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20241029) 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, 3373501 + ... + 3373506.

It is an arithmetic number, because the mean of its divisors is an integer number (6747008).

Almost surely, 2^20241021 is an apocalyptic number.

It is an amenable number.

20241021 is a deficient number, since it is larger than the sum of its proper divisors (6747011).

20241021 is an equidigital number, since it uses as much as digits as its factorization.

20241021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6747010.

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 20241021 is about 4499.0022227156. The cubic root of 20241021 is about 272.5277967324.

Adding to 20241021 its reverse (12014202), we get a palindrome (32255223).

The spelling of 20241021 in words is "twenty million, two hundred forty-one thousand, twenty-one".