20424457 has 4 divisors (see below), whose sum is σ = 20500096. Its totient is φ = 20348820.

The previous prime is 20424431. The next prime is 20424491. The reversal of 20424457 is 75442402.

It is a happy number.

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 a cyclic number.

It is not a de Polignac number, because 20424457 - 2⁷ = 20424329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20424427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37413 + ... + 37954.

It is an arithmetic number, because the mean of its divisors is an integer number (5125024).

Almost surely, 2^20424457 is an apocalyptic number.

It is an amenable number.

20424457 is a deficient number, since it is larger than the sum of its proper divisors (75639).

20424457 is an equidigital number, since it uses as much as digits as its factorization.

20424457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75638.

The product of its (nonzero) digits is 8960, while the sum is 28.

The square root of 20424457 is about 4519.3425406800. The cubic root of 20424457 is about 273.3485910909.

Adding to 20424457 its reverse (75442402), we get a palindrome (95866859).

The spelling of 20424457 in words is "twenty million, four hundred twenty-four thousand, four hundred fifty-seven".