20450000550 has 144 divisors (see below), whose sum is σ = 59067558720. Its totient is φ = 4668632640.

The previous prime is 20450000539. The next prime is 20450000579. The reversal of 20450000550 is 5500005402.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 10722697 + ... + 10724603.

It is an arithmetic number, because the mean of its divisors is an integer number (410191380).

Almost surely, 2^20450000550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20450000550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29533779360).

20450000550 is an abundant number, since it is smaller than the sum of its proper divisors (38617558170).

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

20450000550 is a wasteful number, since it uses less digits than its factorization.

20450000550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3395 (or 3383 counting only the distinct ones).

The product of its (nonzero) digits is 1000, while the sum is 21.

Adding to 20450000550 its reverse (5500005402), we get a palindrome (25950005952).

The spelling of 20450000550 in words is "twenty billion, four hundred fifty million, five hundred fifty", and thus it is an aban number.