649989 has 6 divisors (see below), whose sum is σ = 938886. Its totient is φ = 433320.

The previous prime is 649981. The next prime is 649991. The reversal of 649989 is 989946.

649989 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 476100 + 173889 = 690^2 + 417^2 .

It is not a de Polignac number, because 649989 - 2³ = 649981 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (649981) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36102 + ... + 36119.

It is an arithmetic number, because the mean of its divisors is an integer number (156481).

2⁶⁴⁹⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

649989 is a deficient number, since it is larger than the sum of its proper divisors (288897).

649989 is a wasteful number, since it uses less digits than its factorization.

649989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72227 (or 72224 counting only the distinct ones).

The product of its digits is 139968, while the sum is 45.

The square root of 649989 is about 806.2189528906. The cubic root of 649989 is about 86.6234218836.

The spelling of 649989 in words is "six hundred forty-nine thousand, nine hundred eighty-nine".