1216982880 has 288 divisors, whose sum is σ = 4360565664. Its totient is φ = 320495616.

The previous prime is 1216982867. The next prime is 1216982881. The reversal of 1216982880 is 882896121.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216982881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4393302 + ... + 4393578.

It is an arithmetic number, because the mean of its divisors is an integer number (15140853).

Almost surely, 2^1216982880 is an apocalyptic number.

1216982880 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 1216982880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2180282832).

1216982880 is an abundant number, since it is smaller than the sum of its proper divisors (3143582784).

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

1216982880 is a wasteful number, since it uses less digits than its factorization.

1216982880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 420 (or 400 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 45.

The square root of 1216982880 is about 34885.2817101998. The cubic root of 1216982880 is about 1067.6481608365.

The spelling of 1216982880 in words is "one billion, two hundred sixteen million, nine hundred eighty-two thousand, eight hundred eighty".