20424407 has 4 divisors (see below), whose sum is σ = 20976456. Its totient is φ = 19872360.

The previous prime is 20424401. The next prime is 20424409. The reversal of 20424407 is 70442402.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 70442402 = 2 ⋅35221201.

It is a cyclic number.

It is not a de Polignac number, because 20424407 - 2¹⁰ = 20423383 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20424401) 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, 275969 + ... + 276042.

It is an arithmetic number, because the mean of its divisors is an integer number (5244114).

Almost surely, 2^20424407 is an apocalyptic number.

20424407 is a deficient number, since it is larger than the sum of its proper divisors (552049).

20424407 is an equidigital number, since it uses as much as digits as its factorization.

20424407 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 552048.

The product of its (nonzero) digits is 1792, while the sum is 23.

The square root of 20424407 is about 4519.3370088985. The cubic root of 20424407 is about 273.3483680341.

Adding to 20424407 its reverse (70442402), we get a palindrome (90866809).

The spelling of 20424407 in words is "twenty million, four hundred twenty-four thousand, four hundred seven".