66784985512 has 24 divisors (see below), whose sum is σ = 145666232010. Its totient is φ = 28622136480.

The previous prime is 66784985497. The next prime is 66784985591. The reversal of 66784985512 is 21558948766.

It can be written as a sum of positive squares in only one way, i.e., 66783997476 + 988036 = 258426^2 + 994^2 .

It is a Smith number, since the sum of its digits (61) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 85184539 + ... + 85185322.

Almost surely, 2^66784985512 is an apocalyptic number.

It is an amenable number.

66784985512 is an abundant number, since it is smaller than the sum of its proper divisors (78881246498).

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

66784985512 is a wasteful number, since it uses less digits than its factorization.

66784985512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170369881 (or 170369870 counting only the distinct ones).

The product of its digits is 29030400, while the sum is 61.

The spelling of 66784985512 in words is "sixty-six billion, seven hundred eighty-four million, nine hundred eighty-five thousand, five hundred twelve".