1218253920 has 192 divisors, whose sum is σ = 4175769024. Its totient is φ = 296755200.

The previous prime is 1218253909. The next prime is 1218253937. The reversal of 1218253920 is 293528121.

It is a happy number.

It is a super-2 number, since 2×1218253920² = 2968285227190732800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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, 629274 + ... + 631206.

It is an arithmetic number, because the mean of its divisors is an integer number (21748797).

Almost surely, 2^1218253920 is an apocalyptic number.

1218253920 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 1218253920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2087884512).

1218253920 is an abundant number, since it is smaller than the sum of its proper divisors (2957515104).

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

1218253920 is a wasteful number, since it uses less digits than its factorization.

1218253920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2065 (or 2057 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 1218253920 is about 34903.4943809356. The cubic root of 1218253920 is about 1068.0197221736.

The spelling of 1218253920 in words is "one billion, two hundred eighteen million, two hundred fifty-three thousand, nine hundred twenty".