1216655000 has 120 divisors (see below), whose sum is σ = 3134887140. Its totient is φ = 442200000.

The previous prime is 1216654993. The next prime is 1216655003. The reversal of 1216655000 is 5566121.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216655003) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 603995 + ... + 606005.

Almost surely, 2^1216655000 is an apocalyptic number.

1216655000 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 1216655000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1567443570).

1216655000 is an abundant number, since it is smaller than the sum of its proper divisors (1918232140).

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

1216655000 is a wasteful number, since it uses less digits than its factorization.

1216655000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2059 (or 2029 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 1216655000 is about 34880.5819905574. The cubic root of 1216655000 is about 1067.5522701637.

The spelling of 1216655000 in words is "one billion, two hundred sixteen million, six hundred fifty-five thousand".