812187005 has 12 divisors (see below), whose sum is σ = 1133747100. Its totient is φ = 556928064.

The previous prime is 812186993. The next prime is 812187007. The reversal of 812187005 is 500781218.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 471193849 + 340993156 = 21707^2 + 18466^2 .

It is not a de Polignac number, because 812187005 - 2¹² = 812182909 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (812187007) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1657280 + ... + 1657769.

It is an arithmetic number, because the mean of its divisors is an integer number (94478925).

Almost surely, 2^812187005 is an apocalyptic number.

It is an amenable number.

812187005 is a deficient number, since it is larger than the sum of its proper divisors (321560095).

812187005 is a wasteful number, since it uses less digits than its factorization.

812187005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3315068 (or 3315061 counting only the distinct ones).

The product of its (nonzero) digits is 4480, while the sum is 32.

The square root of 812187005 is about 28498.8948031323. The cubic root of 812187005 is about 933.0079525504.

The spelling of 812187005 in words is "eight hundred twelve million, one hundred eighty-seven thousand, five".