20543903506 has 16 divisors (see below), whose sum is σ = 35322633216. Its totient is φ = 8778401856.

The previous prime is 20543903489. The next prime is 20543903507. The reversal of 20543903506 is 60530934502.

It is not an unprimeable number, because it can be changed into a prime (20543903507) 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 7 ways as a sum of consecutive naturals, for example, 2172466 + ... + 2181901.

It is an arithmetic number, because the mean of its divisors is an integer number (2207664576).

Almost surely, 2^20543903506 is an apocalyptic number.

20543903506 is a deficient number, since it is larger than the sum of its proper divisors (14778729710).

20543903506 is a wasteful number, since it uses less digits than its factorization.

20543903506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4354713.

The product of its (nonzero) digits is 97200, while the sum is 37.

The spelling of 20543903506 in words is "twenty billion, five hundred forty-three million, nine hundred three thousand, five hundred six".