640048628 has 6 divisors (see below), whose sum is σ = 1120085106. Its totient is φ = 320024312.

The previous prime is 640048627. The next prime is 640048637. The reversal of 640048628 is 826840046.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 400480144 + 239568484 = 20012^2 + 15478^2 .

It is a junction number, because it is equal to n+sod(n) for n = 640048591 and 640048600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640048621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80006075 + ... + 80006082.

It is an arithmetic number, because the mean of its divisors is an integer number (186680851).

Almost surely, 2^640048628 is an apocalyptic number.

It is an amenable number.

640048628 is a deficient number, since it is larger than the sum of its proper divisors (480036478).

640048628 is a wasteful number, since it uses less digits than its factorization.

640048628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160012161 (or 160012159 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 38.

The square root of 640048628 is about 25299.1823583293. The cubic root of 640048628 is about 861.7957016788.

The spelling of 640048628 in words is "six hundred forty million, forty-eight thousand, six hundred twenty-eight".