811181915712 has 1344 divisors, whose sum is σ = 3011231268864. Its totient is φ = 211527106560.

The previous prime is 811181915707. The next prime is 811181915723. The reversal of 811181915712 is 217519181118.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (1344).

It is a super-2 number, since 2×811181915712² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 7178600968 + ... + 7178601080.

It is an arithmetic number, because the mean of its divisors is an integer number (2240499456).

Almost surely, 2^811181915712 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 811181915712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1505615634432).

811181915712 is an abundant number, since it is smaller than the sum of its proper divisors (2200049353152).

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

811181915712 is a wasteful number, since it uses less digits than its factorization.

811181915712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278 (or 256 counting only the distinct ones).

The product of its digits is 40320, while the sum is 45.

The spelling of 811181915712 in words is "eight hundred eleven billion, one hundred eighty-one million, nine hundred fifteen thousand, seven hundred twelve".