20424501557 has 4 divisors (see below), whose sum is σ = 20428962720. Its totient is φ = 20420040396.

The previous prime is 20424501551. The next prime is 20424501583. The reversal of 20424501557 is 75510542402.

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 20424501557 - 2⁴ = 20424501541 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 (20424501551) 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, 2223707 + ... + 2232872.

It is an arithmetic number, because the mean of its divisors is an integer number (5107240680).

Almost surely, 2^20424501557 is an apocalyptic number.

It is an amenable number.

20424501557 is a deficient number, since it is larger than the sum of its proper divisors (4461163).

20424501557 is an equidigital number, since it uses as much as digits as its factorization.

20424501557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4461162.

The product of its (nonzero) digits is 56000, while the sum is 35.

The spelling of 20424501557 in words is "twenty billion, four hundred twenty-four million, five hundred one thousand, five hundred fifty-seven".