20503161005 has 4 divisors (see below), whose sum is σ = 24603793212. Its totient is φ = 16402528800.

The previous prime is 20503160999. The next prime is 20503161011. The reversal of 20503161005 is 50016130502.

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

It is an interprime number because it is at equal distance from previous prime (20503160999) and next prime (20503161011).

It can be written as a sum of positive squares in 2 ways, for example, as 5328124036 + 15175036969 = 72994^2 + 123187^2 .

It is not a de Polignac number, because 20503161005 - 2⁸ = 20503160749 is a prime.

It is a super-2 number, since 2×20503161005² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2050316096 + ... + 2050316105.

It is an arithmetic number, because the mean of its divisors is an integer number (6150948303).

Almost surely, 2^20503161005 is an apocalyptic number.

It is an amenable number.

20503161005 is a deficient number, since it is larger than the sum of its proper divisors (4100632207).

20503161005 is an equidigital number, since it uses as much as digits as its factorization.

20503161005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4100632206.

The product of its (nonzero) digits is 900, while the sum is 23.

Adding to 20503161005 its reverse (50016130502), we get a palindrome (70519291507).

The spelling of 20503161005 in words is "twenty billion, five hundred three million, one hundred sixty-one thousand, five".