66789117 has 20 divisors (see below), whose sum is σ = 103215420. Its totient is φ = 42989184.

The previous prime is 66789109. The next prime is 66789127. The reversal of 66789117 is 71198766.

It can be written as a sum of positive squares in 2 ways, for example, as 30536676 + 36252441 = 5526^2 + 6021^2 .

It is not a de Polignac number, because 66789117 - 2³ = 66789109 is a prime.

It is a super-2 number, since 2×66789117² = 8921572299279378, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66789127) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 11868 + ... + 16565.

It is an arithmetic number, because the mean of its divisors is an integer number (5160771).

Almost surely, 2^66789117 is an apocalyptic number.

It is an amenable number.

66789117 is a deficient number, since it is larger than the sum of its proper divisors (36426303).

66789117 is a wasteful number, since it uses less digits than its factorization.

66789117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28474 (or 28465 counting only the distinct ones).

The product of its digits is 127008, while the sum is 45.

The square root of 66789117 is about 8172.4608900869. The cubic root of 66789117 is about 405.7282370853.

The spelling of 66789117 in words is "sixty-six million, seven hundred eighty-nine thousand, one hundred seventeen".