81227830320 has 800 divisors, whose sum is σ = 350070927360. Its totient is φ = 16997713920.

The previous prime is 81227830309. The next prime is 81227830337. The reversal of 81227830320 is 2303872218.

It is a happy number.

81227830320 is a `hidden beast` number, since 81 + 2 + 278 + 303 + 2 + 0 = 666.

It is a super-2 number, since 2×81227830320² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 81965025 + ... + 81966015.

Almost surely, 2^81227830320 is an apocalyptic number.

81227830320 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 81227830320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (175035463680).

81227830320 is an abundant number, since it is smaller than the sum of its proper divisors (268843097040).

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

81227830320 is a wasteful number, since it uses less digits than its factorization.

81227830320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1175 (or 1160 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The spelling of 81227830320 in words is "eighty-one billion, two hundred twenty-seven million, eight hundred thirty thousand, three hundred twenty".