66813752 has 8 divisors (see below), whose sum is σ = 125275800. Its totient is φ = 33406872.

The previous prime is 66813739. The next prime is 66813763. The reversal of 66813752 is 25731866.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 4175852 + ... + 4175867.

It is an arithmetic number, because the mean of its divisors is an integer number (15659475).

Almost surely, 2^66813752 is an apocalyptic number.

It is an amenable number.

66813752 is a deficient number, since it is larger than the sum of its proper divisors (58462048).

66813752 is a wasteful number, since it uses less digits than its factorization.

66813752 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8351725 (or 8351721 counting only the distinct ones).

The product of its digits is 60480, while the sum is 38.

The square root of 66813752 is about 8173.9679470867. The cubic root of 66813752 is about 405.7781149044.

The spelling of 66813752 in words is "sixty-six million, eight hundred thirteen thousand, seven hundred fifty-two".