646640227 has 6 divisors (see below), whose sum is σ = 659074052. Its totient is φ = 634436712.

The previous prime is 646640221. The next prime is 646640257. The reversal of 646640227 is 722046646.

646640227 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-646640227 is a prime.

It is a super-2 number, since 2×646640227² = 836287166349223058, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (646640221) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 112293 + ... + 117910.

Almost surely, 2^646640227 is an apocalyptic number.

646640227 is a deficient number, since it is larger than the sum of its proper divisors (12433825).

646640227 is an equidigital number, since it uses as much as digits as its factorization.

646640227 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230309 (or 230256 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 37.

The square root of 646640227 is about 25429.1216324906. The cubic root of 646640227 is about 864.7440306466.

The spelling of 646640227 in words is "six hundred forty-six million, six hundred forty thousand, two hundred twenty-seven".