66918988 has 12 divisors (see below), whose sum is σ = 123271960. Its totient is φ = 31698432.

The previous prime is 66918959. The next prime is 66918989. The reversal of 66918988 is 88981966.

It is not an unprimeable number, because it can be changed into a prime (66918989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 440181 + ... + 440332.

Almost surely, 2^66918988 is an apocalyptic number.

It is an amenable number.

66918988 is a deficient number, since it is larger than the sum of its proper divisors (56352972).

66918988 is a wasteful number, since it uses less digits than its factorization.

66918988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 880536 (or 880534 counting only the distinct ones).

The product of its digits is 1492992, while the sum is 55.

The square root of 66918988 is about 8180.4026795751. The cubic root of 66918988 is about 405.9910454479.

The spelling of 66918988 in words is "sixty-six million, nine hundred eighteen thousand, nine hundred eighty-eight".