812064640 has 64 divisors (see below), whose sum is σ = 1949832000. Its totient is φ = 323405824.

The previous prime is 812064593. The next prime is 812064661. The reversal of 812064640 is 46460218.

It is a tau number, because it is divible by the number of its divisors (64).

It is a zygodrome in base 2.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 150306 + ... + 155614.

It is an arithmetic number, because the mean of its divisors is an integer number (30466125).

Almost surely, 2^812064640 is an apocalyptic number.

812064640 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 812064640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (974916000).

812064640 is an abundant number, since it is smaller than the sum of its proper divisors (1137767360).

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

812064640 is a wasteful number, since it uses less digits than its factorization.

812064640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5567 (or 5555 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 31.

The square root of 812064640 is about 28496.7478846271. The cubic root of 812064640 is about 932.9610941909.

The spelling of 812064640 in words is "eight hundred twelve million, sixty-four thousand, six hundred forty".