20507043566 has 4 divisors (see below), whose sum is σ = 30760565352. Its totient is φ = 10253521782.

The previous prime is 20507043551. The next prime is 20507043587. The reversal of 20507043566 is 66534070502.

It is a semiprime because it is the product of two primes.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 5126760890 + ... + 5126760893.

It is an arithmetic number, because the mean of its divisors is an integer number (7690141338).

Almost surely, 2^20507043566 is an apocalyptic number.

20507043566 is a deficient number, since it is larger than the sum of its proper divisors (10253521786).

20507043566 is a wasteful number, since it uses less digits than its factorization.

20507043566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10253521785.

The product of its (nonzero) digits is 151200, while the sum is 38.

The spelling of 20507043566 in words is "twenty billion, five hundred seven million, forty-three thousand, five hundred sixty-six".