649520 has 40 divisors (see below), whose sum is σ = 1580256. Its totient is φ = 247808.

The previous prime is 649511. The next prime is 649529. The reversal of 649520 is 25946.

It is an interprime number because it is at equal distance from previous prime (649511) and next prime (649529).

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 649520.

It is not an unprimeable number, because it can be changed into a prime (649529) by changing a digit.

649520 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 7 ways as a sum of consecutive naturals, for example, 1664 + ... + 2016.

2⁶⁴⁹⁵²⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 649520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (790128).

649520 is an abundant number, since it is smaller than the sum of its proper divisors (930736).

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

649520 is a wasteful number, since it uses less digits than its factorization.

649520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 389 (or 383 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 649520 is about 805.9280364896. The cubic root of 649520 is about 86.6025824745.

The spelling of 649520 in words is "six hundred forty-nine thousand, five hundred twenty".