812066186640 has 80 divisors (see below), whose sum is σ = 2598611821056. Its totient is φ = 209565465600.

The previous prime is 812066186627. The next prime is 812066186641. The reversal of 812066186640 is 46681660218.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 812066186640.

It is not an unprimeable number, because it can be changed into a prime (812066186641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 54566901 + ... + 54581780.

Almost surely, 2^812066186640 is an apocalyptic number.

812066186640 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

812066186640 is an abundant number, since it is smaller than the sum of its proper divisors (1786545634416).

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

812066186640 is a wasteful number, since it uses less digits than its factorization.

812066186640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109148728 (or 109148722 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 48.

The spelling of 812066186640 in words is "eight hundred twelve billion, sixty-six million, one hundred eighty-six thousand, six hundred forty".