2131808 has 48 divisors (see below), whose sum is σ = 4967424. Its totient is φ = 881280.

The previous prime is 2131799. The next prime is 2131813. The reversal of 2131808 is 8081312.

It is a hoax number, since the sum of its digits (23) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 6791 + ... + 7097.

It is an arithmetic number, because the mean of its divisors is an integer number (103488).

2^2131808 is an apocalyptic number.

2131808 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2131808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2483712).

2131808 is an abundant number, since it is smaller than the sum of its proper divisors (2835616).

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

2131808 is a wasteful number, since it uses less digits than its factorization.

2131808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 355 (or 347 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 23.

The square root of 2131808 is about 1460.0712311391. The cubic root of 2131808 is about 128.7012295251.

The spelling of 2131808 in words is "two million, one hundred thirty-one thousand, eight hundred eight".