2051816 has 32 divisors (see below), whose sum is σ = 4204200. Its totient is φ = 933120.

The previous prime is 2051801. The next prime is 2051821. The reversal of 2051816 is 6181502.

It can be written as a sum of positive squares in 4 ways, for example, as 940900 + 1110916 = 970^2 + 1054^2 .

It is a junction number, because it is equal to n+sod(n) for n = 2051791 and 2051800.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11246 + ... + 11426.

2^2051816 is an apocalyptic number.

2051816 is a gapful number since it is divisible by the number (26) 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 2051816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2102100).

2051816 is an abundant number, since it is smaller than the sum of its proper divisors (2152384).

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

2051816 is a wasteful number, since it uses less digits than its factorization.

2051816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309 (or 305 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 23.

The square root of 2051816 is about 1432.4161406519. The cubic root of 2051816 is about 127.0709092097.

The spelling of 2051816 in words is "two million, fifty-one thousand, eight hundred sixteen".