1216515356 has 96 divisors (see below), whose sum is σ = 2728320000. Its totient is φ = 472215744.

The previous prime is 1216515353. The next prime is 1216515367. The reversal of 1216515356 is 6535156121.

It is a super-2 number, since 2×1216515356² = 2959819222767613472, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216515353) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 598550 + ... + 600578.

It is an arithmetic number, because the mean of its divisors is an integer number (28420000).

Almost surely, 2^1216515356 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1216515356, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1364160000).

1216515356 is an abundant number, since it is smaller than the sum of its proper divisors (1511804644).

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

1216515356 is a wasteful number, since it uses less digits than its factorization.

1216515356 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2096 (or 2080 counting only the distinct ones).

The product of its digits is 27000, while the sum is 35.

The square root of 1216515356 is about 34878.5801889928. The cubic root of 1216515356 is about 1067.5114251218.

The spelling of 1216515356 in words is "one billion, two hundred sixteen million, five hundred fifteen thousand, three hundred fifty-six".