1721600 has 54 divisors (see below), whose sum is σ = 4277070. Its totient is φ = 686080.

The previous prime is 1721593. The next prime is 1721633. The reversal of 1721600 is 61271.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 256 + 1721344 = 16^2 + 1312^2 .

It is a nialpdrome in base 11.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6266 + ... + 6534.

It is an arithmetic number, because the mean of its divisors is an integer number (79205).

2^1721600 is an apocalyptic number.

1721600 is a gapful number since it is divisible by the number (10) 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 1721600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2138535).

1721600 is an abundant number, since it is smaller than the sum of its proper divisors (2555470).

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

1721600 is an equidigital number, since it uses as much as digits as its factorization.

1721600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 295 (or 276 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 17.

The square root of 1721600 is about 1312.0975573485. The cubic root of 1721600 is about 119.8516685756.

Adding to 1721600 its reverse (61271), we get a palindrome (1782871).

The spelling of 1721600 in words is "one million, seven hundred twenty-one thousand, six hundred".