812563956 has 144 divisors (see below), whose sum is σ = 2250189760. Its totient is φ = 246343680.

The previous prime is 812563951. The next prime is 812563957. The reversal of 812563956 is 659365218.

812563956 is a `hidden beast` number, since 8 + 1 + 2 + 5 + 639 + 5 + 6 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (812563951) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2454711 + ... + 2455041.

Almost surely, 2^812563956 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 812563956, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1125094880).

812563956 is an abundant number, since it is smaller than the sum of its proper divisors (1437625804).

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

812563956 is a wasteful number, since it uses less digits than its factorization.

812563956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 494 (or 489 counting only the distinct ones).

The product of its digits is 388800, while the sum is 45.

The square root of 812563956 is about 28505.5074678561. The cubic root of 812563956 is about 933.1522723038.

The spelling of 812563956 in words is "eight hundred twelve million, five hundred sixty-three thousand, nine hundred fifty-six".