66511879 has 8 divisors (see below), whose sum is σ = 76275360. Its totient is φ = 56813856.

The previous prime is 66511867. The next prime is 66511891. The reversal of 66511879 is 97811566.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (66511867) and next prime (66511891).

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

It is a cyclic number.

It is not a de Polignac number, because 66511879 - 2⁷ = 66511751 is a prime.

It is a super-2 number, since 2×66511879² = 8847660096221282, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66511859) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14164 + ... + 18265.

It is an arithmetic number, because the mean of its divisors is an integer number (9534420).

Almost surely, 2^66511879 is an apocalyptic number.

66511879 is a deficient number, since it is larger than the sum of its proper divisors (9763481).

66511879 is a wasteful number, since it uses less digits than its factorization.

66511879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32729.

The product of its digits is 90720, while the sum is 43.

The square root of 66511879 is about 8155.4815308478. The cubic root of 66511879 is about 405.1660732314.

It can be divided in two parts, 665 and 11879, that added together give a square (12544 = 112²).

The spelling of 66511879 in words is "sixty-six million, five hundred eleven thousand, eight hundred seventy-nine".