66783725 has 12 divisors (see below), whose sum is σ = 83634900. Its totient is φ = 52896000.

The previous prime is 66783713. The next prime is 66783733. The reversal of 66783725 is 52738766.

It can be written as a sum of positive squares in 6 ways, for example, as 426409 + 66357316 = 653^2 + 8146^2 .

It is a de Polignac number, because none of the positive numbers 2^k-66783725 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10700 + ... + 15749.

It is an arithmetic number, because the mean of its divisors is an integer number (6969575).

Almost surely, 2^66783725 is an apocalyptic number.

It is an amenable number.

66783725 is a deficient number, since it is larger than the sum of its proper divisors (16851175).

66783725 is a wasteful number, since it uses less digits than its factorization.

66783725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26560 (or 26555 counting only the distinct ones).

The product of its digits is 423360, while the sum is 44.

The square root of 66783725 is about 8172.1309950343. The cubic root of 66783725 is about 405.7173184126.

The spelling of 66783725 in words is "sixty-six million, seven hundred eighty-three thousand, seven hundred twenty-five".