645206066 has 32 divisors (see below), whose sum is σ = 1081019520. Its totient is φ = 287020800.

The previous prime is 645206063. The next prime is 645206071. The reversal of 645206066 is 660602546.

It is not an unprimeable number, because it can be changed into a prime (645206063) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 426251 + ... + 427761.

It is an arithmetic number, because the mean of its divisors is an integer number (33781860).

Almost surely, 2^645206066 is an apocalyptic number.

645206066 is a deficient number, since it is larger than the sum of its proper divisors (435813454).

645206066 is a wasteful number, since it uses less digits than its factorization.

645206066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2210.

The product of its (nonzero) digits is 51840, while the sum is 35.

The square root of 645206066 is about 25400.9067948371. The cubic root of 645206066 is about 864.1042621449.

The spelling of 645206066 in words is "six hundred forty-five million, two hundred six thousand, sixty-six".