2051640 has 96 divisors (see below), whose sum is σ = 6879600. Its totient is φ = 529920.

The previous prime is 2051629. The next prime is 2051641. The reversal of 2051640 is 461502.

It is a happy number.

2051640 is a `hidden beast` number, since 20 + 5 + 1 + 640 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2051641) 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, 14691 + ... + 14829.

2^2051640 is an apocalyptic number.

2051640 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 2051640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3439800).

2051640 is an abundant number, since it is smaller than the sum of its proper divisors (4827960).

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

2051640 is a wasteful number, since it uses less digits than its factorization.

2051640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 197 (or 190 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 2051640 is about 1432.3547046734. The cubic root of 2051640 is about 127.0672758236.

The spelling of 2051640 in words is "two million, fifty-one thousand, six hundred forty".