812155120 has 40 divisors (see below), whose sum is σ = 2158013664. Its totient is φ = 278452992.

The previous prime is 812155117. The next prime is 812155129. The reversal of 812155120 is 21551218.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (812155129) 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, 724579 + ... + 725698.

Almost surely, 2^812155120 is an apocalyptic number.

812155120 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

812155120 is an abundant number, since it is smaller than the sum of its proper divisors (1345858544).

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

812155120 is a wasteful number, since it uses less digits than its factorization.

812155120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1450297 (or 1450291 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 25.

The square root of 812155120 is about 28498.3353899837. The cubic root of 812155120 is about 932.9957429863.

The spelling of 812155120 in words is "eight hundred twelve million, one hundred fifty-five thousand, one hundred twenty".