649740 has 144 divisors (see below), whose sum is σ = 2413152. Its totient is φ = 129024.

The previous prime is 649739. The next prime is 649751. The reversal of 649740 is 47946.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 649698 and 649707.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 649740.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 38212 + ... + 38228.

It is an arithmetic number, because the mean of its divisors is an integer number (16758).

2⁶⁴⁹⁷⁴⁰ is an apocalyptic number.

649740 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 649740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1206576).

649740 is an abundant number, since it is smaller than the sum of its proper divisors (1763412).

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

649740 is a wasteful number, since it uses less digits than its factorization.

649740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56 (or 47 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 649740 is about 806.0645135471. The cubic root of 649740 is about 86.6123591390.

The spelling of 649740 in words is "six hundred forty-nine thousand, seven hundred forty".