640484650 has 36 divisors (see below), whose sum is σ = 1290006162. Its totient is φ = 236483520.

The previous prime is 640484629. The next prime is 640484653. The reversal of 640484650 is 56484046.

It can be written as a sum of positive squares in 9 ways, for example, as 40401 + 640444249 = 201^2 + 25307^2 .

It is not an unprimeable number, because it can be changed into a prime (640484653) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 29449 + ... + 46348.

Almost surely, 2^640484650 is an apocalyptic number.

640484650 is an abundant number, since it is smaller than the sum of its proper divisors (649521512).

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

640484650 is a wasteful number, since it uses less digits than its factorization.

640484650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75835 (or 75817 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 37.

The square root of 640484650 is about 25307.7982052963. The cubic root of 640484650 is about 861.9913517040.

The spelling of 640484650 in words is "six hundred forty million, four hundred eighty-four thousand, six hundred fifty".