20511345536 has 64 divisors (see below), whose sum is σ = 46515427200. Its totient is φ = 8917962240.

The previous prime is 20511345527. The next prime is 20511345577. The reversal of 20511345536 is 63554311502.

It is a tau number, because it is divible by the number of its divisors (64).

It is a junction number, because it is equal to n+sod(n) for n = 20511345496 and 20511345505.

It is a congruent number.

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 in 7 ways as a sum of consecutive naturals, for example, 284306 + ... + 349073.

It is an arithmetic number, because the mean of its divisors is an integer number (726803550).

Almost surely, 2^20511345536 is an apocalyptic number.

It is an amenable number.

20511345536 is an abundant number, since it is smaller than the sum of its proper divisors (26004081664).

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

20511345536 is a wasteful number, since it uses less digits than its factorization.

20511345536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 633427 (or 633415 counting only the distinct ones).

The product of its (nonzero) digits is 54000, while the sum is 35.

The spelling of 20511345536 in words is "twenty billion, five hundred eleven million, three hundred forty-five thousand, five hundred thirty-six".