2131604 has 12 divisors (see below), whose sum is σ = 3765300. Its totient is φ = 1055808.

The previous prime is 2131603. The next prime is 2131609. The reversal of 2131604 is 4061312.

It can be written as a sum of positive squares in 2 ways, for example, as 1488400 + 643204 = 1220^2 + 802^2 .

It is a super-2 number, since 2×2131604² = 9087471225632, which contains 22 as substring.

It is a zygodrome in base 3.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2131601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2009 + ... + 2880.

It is an arithmetic number, because the mean of its divisors is an integer number (313775).

2^2131604 is an apocalyptic number.

It is an amenable number.

2131604 is a deficient number, since it is larger than the sum of its proper divisors (1633696).

2131604 is a wasteful number, since it uses less digits than its factorization.

2131604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5002 (or 5000 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 2131604 is about 1460.0013698624. The cubic root of 2131604 is about 128.6971241071.

Adding to 2131604 its reverse (4061312), we get a palindrome (6192916).

The spelling of 2131604 in words is "two million, one hundred thirty-one thousand, six hundred four".