66778143471 has 16 divisors (see below), whose sum is σ = 106540628320. Its totient is φ = 41094241920.

The previous prime is 66778143469. The next prime is 66778143473. The reversal of 66778143471 is 17434187766.

It is a happy number.

66778143471 is a `hidden beast` number, since 6 + 67 + 7 + 81 + 434 + 71 = 666.

It is an interprime number because it is at equal distance from previous prime (66778143469) and next prime (66778143473).

It is not a de Polignac number, because 66778143471 - 2¹ = 66778143469 is a prime.

It is a super-3 number, since 3×66778143471³ (a number of 33 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66778143473) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 95125210 + ... + 95125911.

It is an arithmetic number, because the mean of its divisors is an integer number (6658789270).

Almost surely, 2^66778143471 is an apocalyptic number.

66778143471 is a deficient number, since it is larger than the sum of its proper divisors (39762484849).

66778143471 is a wasteful number, since it uses less digits than its factorization.

66778143471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 190251143 (or 190251137 counting only the distinct ones).

The product of its digits is 4741632, while the sum is 54.

The spelling of 66778143471 in words is "sixty-six billion, seven hundred seventy-eight million, one hundred forty-three thousand, four hundred seventy-one".