20424021 has 8 divisors (see below), whose sum is σ = 28833984. Its totient is φ = 12815040.

The previous prime is 20423989. The next prime is 20424043. The reversal of 20424021 is 12042402.

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

It is not a de Polignac number, because 20424021 - 2⁵ = 20423989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20424421) 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, 200185 + ... + 200286.

It is an arithmetic number, because the mean of its divisors is an integer number (3604248).

Almost surely, 2^20424021 is an apocalyptic number.

It is an amenable number.

20424021 is a deficient number, since it is larger than the sum of its proper divisors (8409963).

20424021 is a wasteful number, since it uses less digits than its factorization.

20424021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400491.

The product of its (nonzero) digits is 128, while the sum is 15.

The square root of 20424021 is about 4519.2943033177. The cubic root of 20424021 is about 273.3466460235.

Adding to 20424021 its reverse (12042402), we get a palindrome (32466423).

The spelling of 20424021 in words is "twenty million, four hundred twenty-four thousand, twenty-one".