66397690 has 8 divisors (see below), whose sum is σ = 119515860. Its totient is φ = 26559072.

The previous prime is 66397687. The next prime is 66397717. The reversal of 66397690 is 9679366.

It can be written as a sum of positive squares in 2 ways, for example, as 63345681 + 3052009 = 7959^2 + 1747^2 .

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

It is a super-2 number, since 2×66397690² = 8817306474672200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 66397690.

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, 3319875 + ... + 3319894.

Almost surely, 2^66397690 is an apocalyptic number.

66397690 is a deficient number, since it is larger than the sum of its proper divisors (53118170).

66397690 is a wasteful number, since it uses less digits than its factorization.

66397690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6639776.

The product of its (nonzero) digits is 367416, while the sum is 46.

The square root of 66397690 is about 8148.4777719523. The cubic root of 66397690 is about 404.9340745205.

The spelling of 66397690 in words is "sixty-six million, three hundred ninety-seven thousand, six hundred ninety".