15565566500 has 96 divisors (see below), whose sum is σ = 37130026752. Its totient is φ = 5653440000.

The previous prime is 15565566491. The next prime is 15565566521. The reversal of 15565566500 is 566556551.

It is a Harshad number since it is a multiple of its sum of digits (44).

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 31 ways as a sum of consecutive naturals, for example, 8309564 + ... + 8311436.

It is an arithmetic number, because the mean of its divisors is an integer number (386771112).

Almost surely, 2^15565566500 is an apocalyptic number.

15565566500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15565566500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18565013376).

15565566500 is an abundant number, since it is smaller than the sum of its proper divisors (21564460252).

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

15565566500 is a wasteful number, since it uses less digits than its factorization.

15565566500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3414 (or 3402 counting only the distinct ones).

The product of its (nonzero) digits is 675000, while the sum is 44.

The spelling of 15565566500 in words is "fifteen billion, five hundred sixty-five million, five hundred sixty-six thousand, five hundred".