1220351550 has 144 divisors (see below), whose sum is σ = 3377033856. Its totient is φ = 291368000.

The previous prime is 1220351537. The next prime is 1220351557. The reversal of 1220351550 is 551530221.

It is a happy number.

1220351550 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 1220351550.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220351557) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1288177 + ... + 1289123.

It is an arithmetic number, because the mean of its divisors is an integer number (23451624).

Almost surely, 2^1220351550 is an apocalyptic number.

1220351550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1220351550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1688516928).

1220351550 is an abundant number, since it is smaller than the sum of its proper divisors (2156682306).

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

1220351550 is a wasteful number, since it uses less digits than its factorization.

1220351550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1055 (or 1039 counting only the distinct ones).

The product of its (nonzero) digits is 1500, while the sum is 24.

The square root of 1220351550 is about 34933.5304542785. The cubic root of 1220351550 is about 1068.6323546164.

Adding to 1220351550 its reverse (551530221), we get a palindrome (1771881771).

The spelling of 1220351550 in words is "one billion, two hundred twenty million, three hundred fifty-one thousand, five hundred fifty".