66687604 has 6 divisors (see below), whose sum is σ = 116703314. Its totient is φ = 33343800.

The previous prime is 66687581. The next prime is 66687619. The reversal of 66687604 is 40678666.

It can be written as a sum of positive squares in only one way, i.e., 59136100 + 7551504 = 7690^2 + 2748^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8335947 + ... + 8335954.

Almost surely, 2^66687604 is an apocalyptic number.

It is an amenable number.

66687604 is a deficient number, since it is larger than the sum of its proper divisors (50015710).

66687604 is a wasteful number, since it uses less digits than its factorization.

66687604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16671905 (or 16671903 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 43.

The square root of 66687604 is about 8166.2478532065. The cubic root of 66687604 is about 405.5225769588.

The spelling of 66687604 in words is "sixty-six million, six hundred eighty-seven thousand, six hundred four".