812853640 has 64 divisors (see below), whose sum is σ = 1941453360. Its totient is φ = 305233920.

The previous prime is 812853637. The next prime is 812853677. The reversal of 812853640 is 46358218.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 436726404 + 376127236 = 20898^2 + 19394^2 .

It is a super-2 number, since 2×812853640² = 1321462080122499200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 812853640.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 312184 + ... + 314776.

Almost surely, 2^812853640 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 812853640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (970726680).

812853640 is an abundant number, since it is smaller than the sum of its proper divisors (1128599720).

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

812853640 is a wasteful number, since it uses less digits than its factorization.

812853640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3082 (or 3078 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 37.

The square root of 812853640 is about 28510.5882085937. The cubic root of 812853640 is about 933.2631506184.

The spelling of 812853640 in words is "eight hundred twelve million, eight hundred fifty-three thousand, six hundred forty".