811218240 has 560 divisors, whose sum is σ = 3505151232. Its totient is φ = 173850624.

The previous prime is 811218227. The next prime is 811218269. The reversal of 811218240 is 42812118.

It is a tau number, because it is divible by the number of its divisors (560).

It is a Harshad number since it is a multiple of its sum of digits (27).

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 79 ways as a sum of consecutive naturals, for example, 3084349 + ... + 3084611.

Almost surely, 2^811218240 is an apocalyptic number.

811218240 is a gapful number since it is divisible by the number (80) 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 811218240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1752575616).

811218240 is an abundant number, since it is smaller than the sum of its proper divisors (2693932992).

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

811218240 is a wasteful number, since it uses less digits than its factorization.

811218240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316 (or 297 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 27.

The square root of 811218240 is about 28481.8931955023. The cubic root of 811218240 is about 932.6368454636.

The spelling of 811218240 in words is "eight hundred eleven million, two hundred eighteen thousand, two hundred forty".