1220818550 has 48 divisors (see below), whose sum is σ = 2604556512. Its totient is φ = 417043200.

The previous prime is 1220818549. The next prime is 1220818553. The reversal of 1220818550 is 558180221.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220818553) 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, 92144 + ... + 104556.

It is an arithmetic number, because the mean of its divisors is an integer number (54261594).

Almost surely, 2^1220818550 is an apocalyptic number.

1220818550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1220818550 is an abundant number, since it is smaller than the sum of its proper divisors (1383737962).

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

1220818550 is a wasteful number, since it uses less digits than its factorization.

1220818550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12713 (or 12708 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 32.

The square root of 1220818550 is about 34940.2139375248. The cubic root of 1220818550 is about 1068.7686507694.

Adding to 1220818550 its reverse (558180221), we get a palindrome (1778998771).

The spelling of 1220818550 in words is "one billion, two hundred twenty million, eight hundred eighteen thousand, five hundred fifty".