812139156 has 24 divisors (see below), whose sum is σ = 2105546240. Its totient is φ = 270713016.

The previous prime is 812139143. The next prime is 812139157. The reversal of 812139156 is 651931218.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 812139156.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (812139157) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3759796 + ... + 3760011.

Almost surely, 2^812139156 is an apocalyptic number.

It is an amenable number.

812139156 is an abundant number, since it is smaller than the sum of its proper divisors (1293407084).

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

812139156 is a wasteful number, since it uses less digits than its factorization.

812139156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7519820 (or 7519812 counting only the distinct ones).

The product of its digits is 12960, while the sum is 36.

The square root of 812139156 is about 28498.0553020728. The cubic root of 812139156 is about 932.9896298513.

The spelling of 812139156 in words is "eight hundred twelve million, one hundred thirty-nine thousand, one hundred fifty-six".