2091609 has 32 divisors (see below), whose sum is σ = 3427200. Its totient is φ = 1252800.

The previous prime is 2091599. The next prime is 2091613. The reversal of 2091609 is 9061902.

It is a happy number.

It is not a de Polignac number, because 2091609 - 2⁹ = 2091097 is a prime.

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

It is not an unprimeable number, because it can be changed into a prime (2091619) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20659 + ... + 20759.

It is an arithmetic number, because the mean of its divisors is an integer number (107100).

2^2091609 is an apocalyptic number.

It is an amenable number.

2091609 is a deficient number, since it is larger than the sum of its proper divisors (1335591).

2091609 is a wasteful number, since it uses less digits than its factorization.

2091609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182 (or 176 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 2091609 is about 1446.2396067042. The cubic root of 2091609 is about 127.8871278734.

The spelling of 2091609 in words is "two million, ninety-one thousand, six hundred nine".