66320628 has 24 divisors (see below), whose sum is σ = 168816480. Its totient is φ = 20097120.

The previous prime is 66320627. The next prime is 66320647. The reversal of 66320628 is 82602366.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66320623) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 251083 + ... + 251346.

It is an arithmetic number, because the mean of its divisors is an integer number (7034020).

Almost surely, 2^66320628 is an apocalyptic number.

It is an amenable number.

66320628 is an abundant number, since it is smaller than the sum of its proper divisors (102495852).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66320628 is a wasteful number, since it uses less digits than its factorization.

66320628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 502447 (or 502445 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 33.

The square root of 66320628 is about 8143.7477858784. The cubic root of 66320628 is about 404.7773566701. Note that the first 3 decimals are identical.

The spelling of 66320628 in words is "sixty-six million, three hundred twenty thousand, six hundred twenty-eight".