66778552439 has 8 divisors (see below), whose sum is σ = 67177762560. Its totient is φ = 66379859200.

The previous prime is 66778552427. The next prime is 66778552457. The reversal of 66778552439 is 93425587766.

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

It is a cyclic number.

It is not a de Polignac number, because 66778552439 - 2²⁸ = 66510116983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66778552409) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 131507 + ... + 388395.

It is an arithmetic number, because the mean of its divisors is an integer number (8397220320).

Almost surely, 2^66778552439 is an apocalyptic number.

66778552439 is a deficient number, since it is larger than the sum of its proper divisors (399210121).

66778552439 is a wasteful number, since it uses less digits than its factorization.

66778552439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258441.

The product of its digits is 76204800, while the sum is 62.

The spelling of 66778552439 in words is "sixty-six billion, seven hundred seventy-eight million, five hundred fifty-two thousand, four hundred thirty-nine".