649940 has 12 divisors (see below), whose sum is σ = 1364916. Its totient is φ = 259968.

The previous prime is 649937. The next prime is 649969. The reversal of 649940 is 49946.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 391876 + 258064 = 626^2 + 508^2 .

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 649897 and 649906.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16229 + ... + 16268.

It is an arithmetic number, because the mean of its divisors is an integer number (113743).

2⁶⁴⁹⁹⁴⁰ is an apocalyptic number.

It is an amenable number.

649940 is an abundant number, since it is smaller than the sum of its proper divisors (714976).

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

649940 is a wasteful number, since it uses less digits than its factorization.

649940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32506 (or 32504 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 649940 is about 806.1885635507. The cubic root of 649940 is about 86.6212451010.

The spelling of 649940 in words is "six hundred forty-nine thousand, nine hundred forty".