66380843405 has 4 divisors (see below), whose sum is σ = 79657012092. Its totient is φ = 53104674720.

The previous prime is 66380843393. The next prime is 66380843423. The reversal of 66380843405 is 50434808366.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12016325161 + 54364518244 = 109619^2 + 233162^2 .

It is not a de Polignac number, because 66380843405 - 2¹² = 66380839309 is a prime.

It is a super-3 number, since 3×66380843405³ (a number of 33 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66380843405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6638084336 + ... + 6638084345.

It is an arithmetic number, because the mean of its divisors is an integer number (19914253023).

Almost surely, 2^66380843405 is an apocalyptic number.

It is an amenable number.

66380843405 is a deficient number, since it is larger than the sum of its proper divisors (13276168687).

66380843405 is a wasteful number, since it uses less digits than its factorization.

66380843405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13276168686.

The product of its (nonzero) digits is 1658880, while the sum is 47.

The spelling of 66380843405 in words is "sixty-six billion, three hundred eighty million, eight hundred forty-three thousand, four hundred five".