1216011550 has 24 divisors (see below), whose sum is σ = 2435765976. Its totient is φ = 448988640.

The previous prime is 1216011523. The next prime is 1216011551. The reversal of 1216011550 is 551106121.

It is a happy number.

It is a zygodrome in base 5.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216011551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 934744 + ... + 936043.

It is an arithmetic number, because the mean of its divisors is an integer number (101490249).

Almost surely, 2^1216011550 is an apocalyptic number.

1216011550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1216011550 is an abundant number, since it is smaller than the sum of its proper divisors (1219754426).

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

1216011550 is a wasteful number, since it uses less digits than its factorization.

1216011550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1870812 (or 1870807 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 22.

The square root of 1216011550 is about 34871.3571574150. The cubic root of 1216011550 is about 1067.3640388683.

Adding to 1216011550 its reverse (551106121), we get a palindrome (1767117671).

The spelling of 1216011550 in words is "one billion, two hundred sixteen million, eleven thousand, five hundred fifty".