21545599050 has 120 divisors (see below), whose sum is σ = 60118027200. Its totient is φ = 5721196320.

The previous prime is 21545599037. The next prime is 21545599129. The reversal of 21545599050 is 5099554512.

21545599050 is a `hidden beast` number, since 2 + 1 + 5 + 4 + 5 + 599 + 0 + 50 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a junction number, because it is equal to n+sod(n) for n = 21545598987 and 21545599005.

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 59 ways as a sum of consecutive naturals, for example, 956821 + ... + 979079.

It is an arithmetic number, because the mean of its divisors is an integer number (500983560).

Almost surely, 2^21545599050 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21545599050, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30059013600).

21545599050 is an abundant number, since it is smaller than the sum of its proper divisors (38572428150).

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

21545599050 is a wasteful number, since it uses less digits than its factorization.

21545599050 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22522 (or 22508 counting only the distinct ones).

The product of its (nonzero) digits is 405000, while the sum is 45.

The spelling of 21545599050 in words is "twenty-one billion, five hundred forty-five million, five hundred ninety-nine thousand, fifty".