20500004643 has 16 divisors (see below), whose sum is σ = 27681004800. Its totient is φ = 13493592800.

The previous prime is 20500004639. The next prime is 20500004653. The reversal of 20500004643 is 34640000502.

It is a cyclic number.

It is not a de Polignac number, because 20500004643 - 2² = 20500004639 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20500004653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14548 + ... + 203006.

It is an arithmetic number, because the mean of its divisors is an integer number (1730062800).

Almost surely, 2^20500004643 is an apocalyptic number.

20500004643 is a deficient number, since it is larger than the sum of its proper divisors (7181000157).

20500004643 is a wasteful number, since it uses less digits than its factorization.

20500004643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188922.

The product of its (nonzero) digits is 2880, while the sum is 24.

The spelling of 20500004643 in words is "twenty billion, five hundred million, four thousand, six hundred forty-three".