20535021136 has 60 divisors (see below), whose sum is σ = 46382308128. Its totient is φ = 8781721536.

The previous prime is 20535021113. The next prime is 20535021149. The reversal of 20535021136 is 63112053502.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 338085 + ... + 394171.

Almost surely, 2^20535021136 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20535021136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23191154064).

20535021136 is an abundant number, since it is smaller than the sum of its proper divisors (25847286992).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20535021136 is a wasteful number, since it uses less digits than its factorization.

20535021136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56576 (or 56563 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 28.

Adding to 20535021136 its reverse (63112053502), we get a palindrome (83647074638).

The spelling of 20535021136 in words is "twenty billion, five hundred thirty-five million, twenty-one thousand, one hundred thirty-six".