20503717447 has 4 divisors (see below), whose sum is σ = 20517830200. Its totient is φ = 20489604696.

The previous prime is 20503717441. The next prime is 20503717519. The reversal of 20503717447 is 74471730502.

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

It is a cyclic number.

It is not a de Polignac number, because 20503717447 - 2³ = 20503717439 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 (20503717441) 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, 7054197 + ... + 7057102.

It is an arithmetic number, because the mean of its divisors is an integer number (5129457550).

Almost surely, 2^20503717447 is an apocalyptic number.

20503717447 is a deficient number, since it is larger than the sum of its proper divisors (14112753).

20503717447 is a wasteful number, since it uses less digits than its factorization.

20503717447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14112752.

The product of its (nonzero) digits is 164640, while the sum is 40.

The spelling of 20503717447 in words is "twenty billion, five hundred three million, seven hundred seventeen thousand, four hundred forty-seven".