1665138 has 16 divisors (see below), whose sum is σ = 3350016. Its totient is φ = 551760.

The previous prime is 1665137. The next prime is 1665143. The reversal of 1665138 is 8315661.

It is not an unprimeable number, because it can be changed into a prime (1665137) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 420 + ... + 1872.

It is an arithmetic number, because the mean of its divisors is an integer number (209376).

2^1665138 is an apocalyptic number.

1665138 is an abundant number, since it is smaller than the sum of its proper divisors (1684878).

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

1665138 is a wasteful number, since it uses less digits than its factorization.

1665138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1649.

The product of its digits is 4320, while the sum is 30.

The square root of 1665138 is about 1290.4022628622. The cubic root of 1665138 is about 118.5268503667.

The spelling of 1665138 in words is "one million, six hundred sixty-five thousand, one hundred thirty-eight".