1668537 has 18 divisors (see below), whose sum is σ = 2612142. Its totient is φ = 1025856.

The previous prime is 1668521. The next prime is 1668539. The reversal of 1668537 is 7358661.

It can be written as a sum of positive squares in 3 ways, for example, as 19881 + 1648656 = 141^2 + 1284^2 .

It is not a de Polignac number, because 1668537 - 2⁴ = 1668521 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1668539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 973 + ... + 2069.

It is an arithmetic number, because the mean of its divisors is an integer number (145119).

2^1668537 is an apocalyptic number.

It is an amenable number.

1668537 is a deficient number, since it is larger than the sum of its proper divisors (943605).

1668537 is a wasteful number, since it uses less digits than its factorization.

1668537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1129 (or 1113 counting only the distinct ones).

The product of its digits is 30240, while the sum is 36.

The square root of 1668537 is about 1291.7186226110. The cubic root of 1668537 is about 118.6074440774.

The spelling of 1668537 in words is "one million, six hundred sixty-eight thousand, five hundred thirty-seven".