1664949 has 16 divisors (see below), whose sum is σ = 2608704. Its totient is φ = 931200.

The previous prime is 1664941. The next prime is 1664959. The reversal of 1664949 is 9494661.

It is not a de Polignac number, because 1664949 - 2³ = 1664941 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Curzon number.

1664949 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1664941) 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 15 ways as a sum of consecutive naturals, for example, 1512 + ... + 2369.

It is an arithmetic number, because the mean of its divisors is an integer number (163044).

2^1664949 is an apocalyptic number.

It is an amenable number.

1664949 is a deficient number, since it is larger than the sum of its proper divisors (943755).

1664949 is a wasteful number, since it uses less digits than its factorization.

1664949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3908.

The product of its digits is 46656, while the sum is 39.

The square root of 1664949 is about 1290.3290278065. The cubic root of 1664949 is about 118.5223657690.

It can be divided in two parts, 166 and 4949, that added together give a palindrome (5115).

The spelling of 1664949 in words is "one million, six hundred sixty-four thousand, nine hundred forty-nine".