20505142143 has 28 divisors (see below), whose sum is σ = 31803807960. Its totient is φ = 13198698576.

The previous prime is 20505142129. The next prime is 20505142181. The reversal of 20505142143 is 34124150502.

20505142143 is a `hidden beast` number, since 2 + 0 + 5 + 0 + 514 + 2 + 143 = 666.

It is not a de Polignac number, because 20505142143 - 2¹⁶ = 20505076607 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20505142543) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 463821 + ... + 506102.

Almost surely, 2^20505142143 is an apocalyptic number.

20505142143 is a deficient number, since it is larger than the sum of its proper divisors (11298665817).

20505142143 is an frugal number, since it uses more digits than its factorization.

20505142143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 969970 (or 969955 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

Adding to 20505142143 its reverse (34124150502), we get a palindrome (54629292645).

The spelling of 20505142143 in words is "twenty billion, five hundred five million, one hundred forty-two thousand, one hundred forty-three".