2151680 has 54 divisors (see below), whose sum is σ = 5282718. Its totient is φ = 839680.

The previous prime is 2151659. The next prime is 2151683. The reversal of 2151680 is 861512.

It can be written as a sum of positive squares in 3 ways, for example, as 123904 + 2027776 = 352^2 + 1424^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2151683) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 52460 + ... + 52500.

2^2151680 is an apocalyptic number.

2151680 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 2151680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2641359).

2151680 is an abundant number, since it is smaller than the sum of its proper divisors (3131038).

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

2151680 is an frugal number, since it uses more digits than its factorization.

2151680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103 (or 48 counting only the distinct ones).

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

The square root of 2151680 is about 1466.8605932399. The cubic root of 2151680 is about 129.0998965808.

The spelling of 2151680 in words is "two million, one hundred fifty-one thousand, six hundred eighty".