66690290 has 8 divisors (see below), whose sum is σ = 120042540. Its totient is φ = 26676112.

The previous prime is 66690287. The next prime is 66690301. The reversal of 66690290 is 9209666.

It can be written as a sum of positive squares in 2 ways, for example, as 66406201 + 284089 = 8149^2 + 533^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3334505 + ... + 3334524.

Almost surely, 2^66690290 is an apocalyptic number.

66690290 is a deficient number, since it is larger than the sum of its proper divisors (53352250).

66690290 is a wasteful number, since it uses less digits than its factorization.

66690290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6669036.

The product of its (nonzero) digits is 34992, while the sum is 38.

The square root of 66690290 is about 8166.4123089641. The cubic root of 66690290 is about 405.5280213440.

The spelling of 66690290 in words is "sixty-six million, six hundred ninety thousand, two hundred ninety".