2131506 has 24 divisors (see below), whose sum is σ = 4974060. Its totient is φ = 655776.

The previous prime is 2131483. The next prime is 2131513. The reversal of 2131506 is 6051312.

It can be written as a sum of positive squares in 2 ways, for example, as 1782225 + 349281 = 1335^2 + 591^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon 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 11 ways as a sum of consecutive naturals, for example, 4321 + ... + 4788.

2^2131506 is an apocalyptic number.

2131506 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

2131506 is an abundant number, since it is smaller than the sum of its proper divisors (2842554).

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

2131506 is a wasteful number, since it uses less digits than its factorization.

2131506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9130 (or 9127 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

The square root of 2131506 is about 1459.9678078643. The cubic root of 2131506 is about 128.6951518034.

Adding to 2131506 its reverse (6051312), we get a palindrome (8182818).

The spelling of 2131506 in words is "two million, one hundred thirty-one thousand, five hundred six".