640484066 has 8 divisors (see below), whose sum is σ = 966034524. Its totient is φ = 318472560.

The previous prime is 640484041. The next prime is 640484071. The reversal of 640484066 is 660484046.

It can be written as a sum of positive squares in 2 ways, for example, as 638320225 + 2163841 = 25265^2 + 1471^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 884285 + ... + 885008.

Almost surely, 2^640484066 is an apocalyptic number.

640484066 is a deficient number, since it is larger than the sum of its proper divisors (325550458).

640484066 is a wasteful number, since it uses less digits than its factorization.

640484066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1769476.

The product of its (nonzero) digits is 110592, while the sum is 38.

The square root of 640484066 is about 25307.7866673481. The cubic root of 640484066 is about 861.9910897133.

The spelling of 640484066 in words is "six hundred forty million, four hundred eighty-four thousand, sixty-six".