812259840 has 320 divisors, whose sum is σ = 3075874560. Its totient is φ = 178913280.

The previous prime is 812259839. The next prime is 812259841. The reversal of 812259840 is 48952218.

It is an interprime number because it is at equal distance from previous prime (812259839) and next prime (812259841).

It is a tau number, because it is divible by the number of its divisors (320).

It is not an unprimeable number, because it can be changed into a prime (812259841) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1558780 + ... + 1559300.

It is an arithmetic number, because the mean of its divisors is an integer number (9612108).

Almost surely, 2^812259840 is an apocalyptic number.

812259840 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 812259840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1537937280).

812259840 is an abundant number, since it is smaller than the sum of its proper divisors (2263614720).

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

812259840 is a wasteful number, since it uses less digits than its factorization.

812259840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 583 (or 567 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 39.

The square root of 812259840 is about 28500.1726310561. The cubic root of 812259840 is about 933.0358416952.

The spelling of 812259840 in words is "eight hundred twelve million, two hundred fifty-nine thousand, eight hundred forty".