666630810 has 40 divisors (see below), whose sum is σ = 1792498356. Its totient is φ = 177768000.

The previous prime is 666630799. The next prime is 666630829. The reversal of 666630810 is 18036666.

It can be written as a sum of positive squares in 2 ways, for example, as 561547809 + 105083001 = 23697^2 + 10251^2 .

It is a super-2 number, since 2×666630810² = 888793273682512200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 410691 + ... + 412310.

Almost surely, 2^666630810 is an apocalyptic number.

666630810 is an abundant number, since it is smaller than the sum of its proper divisors (1125867546).

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

666630810 is a wasteful number, since it uses less digits than its factorization.

666630810 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 823020 (or 823011 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 666630810 is about 25819.1946040151. The cubic root of 666630810 is about 873.5648026137.

The spelling of 666630810 in words is "six hundred sixty-six million, six hundred thirty thousand, eight hundred ten".