66210769 has 9 divisors (see below), whose sum is σ = 67716873. Its totient is φ = 64737972.

The previous prime is 66210757. The next prime is 66210779. The reversal of 66210769 is 96701266.

The square root of 66210769 is 8137.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 66210769 - 2⁵ = 66210737 is a prime.

It is a super-2 number, since 2×66210769² = 8767731863142722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66210719) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 642772 + ... + 642874.

It is an arithmetic number, because the mean of its divisors is an integer number (7524097).

Almost surely, 2^66210769 is an apocalyptic number.

66210769 is the 8137-th square number.

66210769 is the 4069-th centered octagonal number.

It is an amenable number.

66210769 is a deficient number, since it is larger than the sum of its proper divisors (1506104).

66210769 is an frugal number, since it uses more digits than its factorization.

66210769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 364 (or 182 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 37.

The cubic root of 66210769 is about 404.5537308625.

The spelling of 66210769 in words is "sixty-six million, two hundred ten thousand, seven hundred sixty-nine".