20305512503 has 4 divisors (see below), whose sum is σ = 20777733768. Its totient is φ = 19833291240.

The previous prime is 20305512497. The next prime is 20305512509. The reversal of 20305512503 is 30521550302.

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 (20305512497) and next prime (20305512509).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20305512503 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 (20305512509) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 236110568 + ... + 236110653.

It is an arithmetic number, because the mean of its divisors is an integer number (5194433442).

Almost surely, 2^20305512503 is an apocalyptic number.

20305512503 is a deficient number, since it is larger than the sum of its proper divisors (472221265).

20305512503 is an equidigital number, since it uses as much as digits as its factorization.

20305512503 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 472221264.

The product of its (nonzero) digits is 4500, while the sum is 26.

The spelling of 20305512503 in words is "twenty billion, three hundred five million, five hundred twelve thousand, five hundred three".