1216825344 has 144 divisors (see below), whose sum is σ = 4016900160. Its totient is φ = 347627520.

The previous prime is 1216825331. The next prime is 1216825349. The reversal of 1216825344 is 4435286121.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1216825299 and 1216825308.

It is not an unprimeable number, because it can be changed into a prime (1216825349) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 124309 + ... + 133739.

It is an arithmetic number, because the mean of its divisors is an integer number (27895140).

Almost surely, 2^1216825344 is an apocalyptic number.

1216825344 is a gapful number since it is divisible by the number (14) 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 1216825344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2008450080).

1216825344 is an abundant number, since it is smaller than the sum of its proper divisors (2800074816).

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

1216825344 is an equidigital number, since it uses as much as digits as its factorization.

1216825344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9466 (or 9443 counting only the distinct ones).

The product of its digits is 46080, while the sum is 36.

The square root of 1216825344 is about 34883.0237221489. The cubic root of 1216825344 is about 1067.6020905421.

The spelling of 1216825344 in words is "one billion, two hundred sixteen million, eight hundred twenty-five thousand, three hundred forty-four".