1664497 has 4 divisors (see below), whose sum is σ = 1667700. Its totient is φ = 1661296.

The previous prime is 1664461. The next prime is 1664501. The reversal of 1664497 is 7944661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7944661 = 17 ⋅467333.

It can be written as a sum of positive squares in 2 ways, for example, as 1018081 + 646416 = 1009^2 + 804^2 .

It is a cyclic number.

It is not a de Polignac number, because 1664497 - 2¹¹ = 1662449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1664407) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 622 + ... + 1927.

It is an arithmetic number, because the mean of its divisors is an integer number (416925).

2^1664497 is an apocalyptic number.

It is an amenable number.

1664497 is a deficient number, since it is larger than the sum of its proper divisors (3203).

1664497 is an equidigital number, since it uses as much as digits as its factorization.

1664497 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3202.

The product of its digits is 36288, while the sum is 37.

The square root of 1664497 is about 1290.1538667926. The cubic root of 1664497 is about 118.5116393227.

The spelling of 1664497 in words is "one million, six hundred sixty-four thousand, four hundred ninety-seven".