648990 has 24 divisors (see below), whose sum is σ = 1687608. Its totient is φ = 173040.

The previous prime is 648971. The next prime is 648997. The reversal of 648990 is 99846.

648990 is a `hidden beast` number, since 648 + 9 + 9 + 0 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (648997) by changing a digit.

648990 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3516 + ... + 3695.

It is an arithmetic number, because the mean of its divisors is an integer number (70317).

2⁶⁴⁸⁹⁹⁰ is an apocalyptic number.

648990 is an abundant number, since it is smaller than the sum of its proper divisors (1038618).

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

648990 is a wasteful number, since it uses less digits than its factorization.

648990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7224 (or 7221 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 648990 is about 805.5991559082. The cubic root of 648990 is about 86.5790205319.

The spelling of 648990 in words is "six hundred forty-eight thousand, nine hundred ninety".