66724805 has 16 divisors (see below), whose sum is σ = 92323584. Its totient is φ = 45346560.

The previous prime is 66724769. The next prime is 66724829. The reversal of 66724805 is 50842766.

It is a happy number.

It is not a de Polignac number, because 66724805 - 2¹⁸ = 66462661 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4481 + ... + 12390.

It is an arithmetic number, because the mean of its divisors is an integer number (5770224).

Almost surely, 2^66724805 is an apocalyptic number.

It is an amenable number.

66724805 is a deficient number, since it is larger than the sum of its proper divisors (25598779).

66724805 is a wasteful number, since it uses less digits than its factorization.

66724805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16996.

The product of its (nonzero) digits is 80640, while the sum is 38.

The square root of 66724805 is about 8168.5252646974. The cubic root of 66724805 is about 405.5979684868.

The spelling of 66724805 in words is "sixty-six million, seven hundred twenty-four thousand, eight hundred five".