1216154816 has 56 divisors (see below), whose sum is σ = 2446782000. Its totient is φ = 599703552.

The previous prime is 1216154803. The next prime is 1216154839. The reversal of 1216154816 is 6184516121.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2436935 + ... + 2437433.

Almost surely, 2^1216154816 is an apocalyptic number.

1216154816 is a gapful number since it is divisible by the number (16) 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 1216154816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1223391000).

1216154816 is an abundant number, since it is smaller than the sum of its proper divisors (1230627184).

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

1216154816 is a wasteful number, since it uses less digits than its factorization.

1216154816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 961 (or 951 counting only the distinct ones).

The product of its digits is 11520, while the sum is 35.

The square root of 1216154816 is about 34873.4113043161. The cubic root of 1216154816 is about 1067.4059548549.

The spelling of 1216154816 in words is "one billion, two hundred sixteen million, one hundred fifty-four thousand, eight hundred sixteen".