1216385000 has 80 divisors (see below), whose sum is σ = 2893323840. Its totient is φ = 479160000.

The previous prime is 1216384963. The next prime is 1216385017. The reversal of 1216385000 is 5836121.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 333185 + ... + 336815.

It is an arithmetic number, because the mean of its divisors is an integer number (36166548).

Almost surely, 2^1216385000 is an apocalyptic number.

1216385000 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 1216385000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1446661920).

1216385000 is an abundant number, since it is smaller than the sum of its proper divisors (1676938840).

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

1216385000 is an equidigital number, since it uses as much as digits as its factorization.

1216385000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3724 (or 3705 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 1216385000 is about 34876.7114275414. The cubic root of 1216385000 is about 1067.4732939440.

The spelling of 1216385000 in words is "one billion, two hundred sixteen million, three hundred eighty-five thousand".