1216905000 has 160 divisors (see below), whose sum is σ = 3925743360. Its totient is φ = 313920000.

The previous prime is 1216904993. The next prime is 1216905007. The reversal of 1216905000 is 5096121.

It is an interprime number because it is at equal distance from previous prime (1216904993) and next prime (1216905007).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (1216905007) 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 39 ways as a sum of consecutive naturals, for example, 463692 + ... + 466308.

It is an arithmetic number, because the mean of its divisors is an integer number (24535896).

Almost surely, 2^1216905000 is an apocalyptic number.

1216905000 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 1216905000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1962871680).

1216905000 is an abundant number, since it is smaller than the sum of its proper divisors (2708838360).

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

1216905000 is a wasteful number, since it uses less digits than its factorization.

1216905000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2677 (or 2658 counting only the distinct ones).

The product of its (nonzero) digits is 540, while the sum is 24.

The square root of 1216905000 is about 34884.1654622839. The cubic root of 1216905000 is about 1067.6253858756.

The spelling of 1216905000 in words is "one billion, two hundred sixteen million, nine hundred five thousand".