20715520565550 has 48 divisors (see below), whose sum is σ = 51430884855552. Its totient is φ = 5518074962400.

The previous prime is 20715520565449. The next prime is 20715520565557. The reversal of 20715520565550 is 5556502551702.

It is a self number, because there is not a number n which added to its sum of digits gives 20715520565550.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20715520565557) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 75661084 + ... + 75934383.

It is an arithmetic number, because the mean of its divisors is an integer number (1071476767824).

Almost surely, 2^{20715520565550} is an apocalyptic number.

20715520565550 is an abundant number, since it is smaller than the sum of its proper divisors (30715364290002).

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

20715520565550 is a wasteful number, since it uses less digits than its factorization.

20715520565550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151596393 (or 151596388 counting only the distinct ones).

The product of its (nonzero) digits is 2625000, while the sum is 48.

The spelling of 20715520565550 in words is "twenty trillion, seven hundred fifteen billion, five hundred twenty million, five hundred sixty-five thousand, five hundred fifty".