649649 has 24 divisors (see below), whose sum is σ = 893760. Its totient is φ = 459360.

The previous prime is 649643. The next prime is 649651. The reversal of 649649 is 946946.

649649 = 238² + 239² + ... + 248².

It is not a de Polignac number, because 649649 - 2⁴ = 649633 is a prime.

It is an Ulam number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (649643) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 10982 + ... + 11040.

It is an arithmetic number, because the mean of its divisors is an integer number (37240).

2⁶⁴⁹⁶⁴⁹ is an apocalyptic number.

It is an amenable number.

649649 is a deficient number, since it is larger than the sum of its proper divisors (244111).

649649 is a wasteful number, since it uses less digits than its factorization.

649649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101 (or 90 counting only the distinct ones).

The product of its digits is 46656, while the sum is 38.

The square root of 649649 is about 806.0080644758. The cubic root of 649649 is about 86.6083154227.

The spelling of 649649 in words is "six hundred forty-nine thousand, six hundred forty-nine".