648120640 has 28 divisors (see below), whose sum is σ = 1543338036. Its totient is φ = 259248128.

The previous prime is 648120617. The next prime is 648120677. The reversal of 648120640 is 46021846.

It can be written as a sum of positive squares in 2 ways, for example, as 340328704 + 307791936 = 18448^2 + 17544^2 .

It is a congruent number.

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, 1012369 + ... + 1013008.

Almost surely, 2^648120640 is an apocalyptic number.

It is an amenable number.

648120640 is an abundant number, since it is smaller than the sum of its proper divisors (895217396).

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

648120640 is a wasteful number, since it uses less digits than its factorization.

648120640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2025394 (or 2025384 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 31.

The square root of 648120640 is about 25458.2136058287. The cubic root of 648120640 is about 865.4034403918.

The spelling of 648120640 in words is "six hundred forty-eight million, one hundred twenty thousand, six hundred forty".