66689026 has 4 divisors (see below), whose sum is σ = 100033542. Its totient is φ = 33344512.

The previous prime is 66689023. The next prime is 66689041. The reversal of 66689026 is 62098666.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 65691025 + 998001 = 8105^2 + 999^2 .

It is not an unprimeable number, because it can be changed into a prime (66689023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16672255 + ... + 16672258.

Almost surely, 2^66689026 is an apocalyptic number.

66689026 is a deficient number, since it is larger than the sum of its proper divisors (33344516).

66689026 is a wasteful number, since it uses less digits than its factorization.

66689026 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33344515.

The product of its (nonzero) digits is 186624, while the sum is 43.

The square root of 66689026 is about 8166.3349184319. The cubic root of 66689026 is about 405.5254592986.

The spelling of 66689026 in words is "sixty-six million, six hundred eighty-nine thousand, twenty-six".