1664540 has 12 divisors (see below), whose sum is σ = 3495576. Its totient is φ = 665808.

The previous prime is 1664501. The next prime is 1664543. The reversal of 1664540 is 454661.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1664543) 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, 41594 + ... + 41633.

It is an arithmetic number, because the mean of its divisors is an integer number (291298).

2^1664540 is an apocalyptic number.

1664540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1664540 is an abundant number, since it is smaller than the sum of its proper divisors (1831036).

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

1664540 is a wasteful number, since it uses less digits than its factorization.

1664540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83236 (or 83234 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 1664540 is about 1290.1705313640. The cubic root of 1664540 is about 118.5126598425.

The spelling of 1664540 in words is "one million, six hundred sixty-four thousand, five hundred forty".