1665140 has 12 divisors (see below), whose sum is σ = 3496836. Its totient is φ = 666048.

The previous prime is 1665137. The next prime is 1665143. The reversal of 1665140 is 415661.

It is an interprime number because it is at equal distance from previous prime (1665137) and next prime (1665143).

It can be written as a sum of positive squares in 2 ways, for example, as 1069156 + 595984 = 1034^2 + 772^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1665143) 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, 41609 + ... + 41648.

It is an arithmetic number, because the mean of its divisors is an integer number (291403).

2^1665140 is an apocalyptic number.

1665140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1665140 is an abundant number, since it is smaller than the sum of its proper divisors (1831696).

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

1665140 is a wasteful number, since it uses less digits than its factorization.

1665140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83266 (or 83264 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 1665140 is about 1290.4030378142. The cubic root of 1665140 is about 118.5268978210.

It can be divided in two parts, 16 and 65140, that added together give a palindrome (65156).

The spelling of 1665140 in words is "one million, six hundred sixty-five thousand, one hundred forty".