1216735520 has 384 divisors, whose sum is σ = 3950456832. Its totient is φ = 341913600.

The previous prime is 1216735517. The next prime is 1216735549. The reversal of 1216735520 is 255376121.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 11371307 + ... + 11371413.

It is an arithmetic number, because the mean of its divisors is an integer number (10287648).

Almost surely, 2^1216735520 is an apocalyptic number.

1216735520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1216735520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1975228416).

1216735520 is an abundant number, since it is smaller than the sum of its proper divisors (2733721312).

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

1216735520 is a wasteful number, since it uses less digits than its factorization.

1216735520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224 (or 216 counting only the distinct ones).

The product of its (nonzero) digits is 12600, while the sum is 32.

The square root of 1216735520 is about 34881.7361953215. The cubic root of 1216735520 is about 1067.5758203655.

The spelling of 1216735520 in words is "one billion, two hundred sixteen million, seven hundred thirty-five thousand, five hundred twenty".