661249 has 8 divisors (see below), whose sum is σ = 709128. Its totient is φ = 614400.

The previous prime is 661237. The next prime is 661253. The reversal of 661249 is 942166.

It can be written as a sum of positive squares in 4 ways, for example, as 378225 + 283024 = 615^2 + 532^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 661249 - 2⁵ = 661217 is a prime.

It is a Duffinian number.

661249 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (661259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1449 + ... + 1849.

It is an arithmetic number, because the mean of its divisors is an integer number (88641).

2⁶⁶¹²⁴⁹ is an apocalyptic number.

It is an amenable number.

661249 is a deficient number, since it is larger than the sum of its proper divisors (47879).

661249 is a wasteful number, since it uses less digits than its factorization.

661249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 515.

The product of its digits is 2592, while the sum is 28.

The square root of 661249 is about 813.1721834888. The cubic root of 661249 is about 87.1207641617.

The spelling of 661249 in words is "six hundred sixty-one thousand, two hundred forty-nine".