649540 has 24 divisors (see below), whose sum is σ = 1395072. Its totient is φ = 253920.

The previous prime is 649529. The next prime is 649541. The reversal of 649540 is 45946.

It is a junction number, because it is equal to n+sod(n) for n = 649499 and 649508.

It is not an unprimeable number, because it can be changed into a prime (649541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 595 + ... + 1285.

It is an arithmetic number, because the mean of its divisors is an integer number (58128).

2⁶⁴⁹⁵⁴⁰ is an apocalyptic number.

It is an amenable number.

649540 is an abundant number, since it is smaller than the sum of its proper divisors (745532).

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

649540 is a wasteful number, since it uses less digits than its factorization.

649540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 747 (or 745 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 649540 is about 805.9404444498. The cubic root of 649540 is about 86.6034713534.

It can be divided in two parts, 64 and 9540, that added together give a square (9604 = 98²).

The spelling of 649540 in words is "six hundred forty-nine thousand, five hundred forty".