66983615 has 4 divisors (see below), whose sum is σ = 80380344. Its totient is φ = 53586888.

The previous prime is 66983611. The next prime is 66983629. The reversal of 66983615 is 51638966.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66983615 - 2² = 66983611 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66983611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6698357 + ... + 6698366.

It is an arithmetic number, because the mean of its divisors is an integer number (20095086).

Almost surely, 2^66983615 is an apocalyptic number.

66983615 is a deficient number, since it is larger than the sum of its proper divisors (13396729).

66983615 is a wasteful number, since it uses less digits than its factorization.

66983615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13396728.

The product of its digits is 233280, while the sum is 44.

The square root of 66983615 is about 8184.3518375006. The cubic root of 66983615 is about 406.1216986559.

The spelling of 66983615 in words is "sixty-six million, nine hundred eighty-three thousand, six hundred fifteen".