1664145 has 40 divisors (see below), whose sum is σ = 3415104. Its totient is φ = 759456.

The previous prime is 1664123. The next prime is 1664227. The reversal of 1664145 is 5414661.

1664145 is a `hidden beast` number, since 16 + 641 + 4 + 5 = 666.

It is not a de Polignac number, because 1664145 - 2⁷ = 1664017 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

1664145 is a lucky number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 2542 + ... + 3128.

2^1664145 is an apocalyptic number.

1664145 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1664145 is an abundant number, since it is smaller than the sum of its proper divisors (1750959).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1664145 is an equidigital number, since it uses as much as digits as its factorization.

1664145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 611 (or 602 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 1664145 is about 1290.0174417426. The cubic root of 1664145 is about 118.5032846390.

The spelling of 1664145 in words is "one million, six hundred sixty-four thousand, one hundred forty-five".