66788899 has 8 divisors (see below), whose sum is σ = 67630320. Its totient is φ = 65953056.

The previous prime is 66788881. The next prime is 66788947. The reversal of 66788899 is 99888766.

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 66788899 - 2⁹ = 66788387 is a prime.

It is a Duffinian number.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (66788809) 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, 25932 + ... + 28390.

It is an arithmetic number, because the mean of its divisors is an integer number (8453790).

Almost surely, 2^66788899 is an apocalyptic number.

66788899 is a deficient number, since it is larger than the sum of its proper divisors (841421).

66788899 is a wasteful number, since it uses less digits than its factorization.

66788899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2789.

The product of its digits is 10450944, while the sum is 61.

The square root of 66788899 is about 8172.4475526001. The cubic root of 66788899 is about 405.7277956519.

The spelling of 66788899 in words is "sixty-six million, seven hundred eighty-eight thousand, eight hundred ninety-nine".