20503133551 has 4 divisors (see below), whose sum is σ = 20503547104. Its totient is φ = 20502720000.

The previous prime is 20503133531. The next prime is 20503133627. The reversal of 20503133551 is 15533130502.

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 20503133551 - 2³³ = 11913198959 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 (20503133531) 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, 120375 + ... + 235576.

It is an arithmetic number, because the mean of its divisors is an integer number (5125886776).

Almost surely, 2^20503133551 is an apocalyptic number.

20503133551 is a deficient number, since it is larger than the sum of its proper divisors (413553).

20503133551 is an equidigital number, since it uses as much as digits as its factorization.

20503133551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 413552.

The product of its (nonzero) digits is 6750, while the sum is 28.

The spelling of 20503133551 in words is "twenty billion, five hundred three million, one hundred thirty-three thousand, five hundred fifty-one".