812132640 has 432 divisors, whose sum is σ = 3137097600. Its totient is φ = 191093760.

The previous prime is 812132623. The next prime is 812132641. The reversal of 812132640 is 46231218.

812132640 is a `hidden beast` number, since 8 + 1 + 2 + 13 + 2 + 640 = 666.

It is not an unprimeable number, because it can be changed into a prime (812132641) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 10280121 + ... + 10280199.

It is an arithmetic number, because the mean of its divisors is an integer number (7261800).

Almost surely, 2^812132640 is an apocalyptic number.

812132640 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 812132640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1568548800).

812132640 is an abundant number, since it is smaller than the sum of its proper divisors (2324964960).

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

812132640 is a wasteful number, since it uses less digits than its factorization.

812132640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181 (or 159 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 812132640 is about 28497.9409782531. The cubic root of 812132640 is about 932.9871346399.

Adding to 812132640 its reverse (46231218), we get a palindrome (858363858).

The spelling of 812132640 in words is "eight hundred twelve million, one hundred thirty-two thousand, six hundred forty".