20535740842 has 4 divisors (see below), whose sum is σ = 30803611266. Its totient is φ = 10267870420.

The previous prime is 20535740837. The next prime is 20535740899. The reversal of 20535740842 is 24804753502.

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

It can be written as a sum of positive squares in only one way, i.e., 16752383761 + 3783357081 = 129431^2 + 61509^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 20535740795 and 20535740804.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5133935209 + ... + 5133935212.

Almost surely, 2^20535740842 is an apocalyptic number.

20535740842 is a deficient number, since it is larger than the sum of its proper divisors (10267870424).

20535740842 is a wasteful number, since it uses less digits than its factorization.

20535740842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10267870423.

The product of its (nonzero) digits is 268800, while the sum is 40.

The spelling of 20535740842 in words is "twenty billion, five hundred thirty-five million, seven hundred forty thousand, eight hundred forty-two".