20643342550 has 12 divisors (see below), whose sum is σ = 38396617236. Its totient is φ = 8257337000.

The previous prime is 20643342409. The next prime is 20643342557. The reversal of 20643342550 is 5524334602.

It is a super-2 number, since 2×20643342550² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20643342557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 206433376 + ... + 206433475.

It is an arithmetic number, because the mean of its divisors is an integer number (3199718103).

Almost surely, 2^20643342550 is an apocalyptic number.

20643342550 is a deficient number, since it is larger than the sum of its proper divisors (17753274686).

20643342550 is a wasteful number, since it uses less digits than its factorization.

20643342550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 412866863 (or 412866858 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 34.

The spelling of 20643342550 in words is "twenty billion, six hundred forty-three million, three hundred forty-two thousand, five hundred fifty".