1216131600 has 240 divisors, whose sum is σ = 4026974400. Its totient is φ = 313589760.

The previous prime is 1216131599. The next prime is 1216131611. The reversal of 1216131600 is 61316121.

It is a tau number, because it is divible by the number of its divisors (240).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6301104 + ... + 6301296.

It is an arithmetic number, because the mean of its divisors is an integer number (16779060).

Almost surely, 2^1216131600 is an apocalyptic number.

1216131600 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 1216131600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2013487200).

1216131600 is an abundant number, since it is smaller than the sum of its proper divisors (2810842800).

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

1216131600 is a wasteful number, since it uses less digits than its factorization.

1216131600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 362 (or 351 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 1216131600 is about 34873.0784416862. The cubic root of 1216131600 is about 1067.3991626675.

Adding to 1216131600 its reverse (61316121), we get a palindrome (1277447721).

The spelling of 1216131600 in words is "one billion, two hundred sixteen million, one hundred thirty-one thousand, six hundred".