2051815680 has 216 divisors, whose sum is σ = 7517378232. Its totient is φ = 514916352.

The previous prime is 2051815679. The next prime is 2051815687. The reversal of 2051815680 is 865181502.

It can be written as a sum of positive squares in 4 ways, for example, as 664402176 + 1387413504 = 25776^2 + 37248^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (2051815687) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 190602 + ... + 201078.

It is an arithmetic number, because the mean of its divisors is an integer number (34802677).

Almost surely, 2^2051815680 is an apocalyptic number.

2051815680 is a gapful number since it is divisible by the number (20) 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 2051815680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3758689116).

2051815680 is an abundant number, since it is smaller than the sum of its proper divisors (5465562552).

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

2051815680 is a wasteful number, since it uses less digits than its factorization.

2051815680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10521 (or 10504 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 36.

The square root of 2051815680 is about 45296.9720842354. The cubic root of 2051815680 is about 1270.7090260376.

The spelling of 2051815680 in words is "two billion, fifty-one million, eight hundred fifteen thousand, six hundred eighty".