66780405698 has 8 divisors (see below), whose sum is σ = 100218021708. Its totient is φ = 33374398464.

The previous prime is 66780405649. The next prime is 66780405701. The reversal of 66780405698 is 89650408766.

It can be written as a sum of positive squares in 2 ways, for example, as 51693933769 + 15086471929 = 227363^2 + 122827^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 7896911 + ... + 7905362.

Almost surely, 2^66780405698 is an apocalyptic number.

66780405698 is a deficient number, since it is larger than the sum of its proper divisors (33437616010).

66780405698 is a wasteful number, since it uses less digits than its factorization.

66780405698 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15804388.

The product of its (nonzero) digits is 17418240, while the sum is 59.

The spelling of 66780405698 in words is "sixty-six billion, seven hundred eighty million, four hundred five thousand, six hundred ninety-eight".