1721536 has 28 divisors (see below), whose sum is σ = 3513328. Its totient is φ = 836352.

The previous prime is 1721521. The next prime is 1721543. The reversal of 1721536 is 6351271.

It is a self number, because there is not a number n which added to its sum of digits gives 1721536.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2005 + ... + 2731.

It is an arithmetic number, because the mean of its divisors is an integer number (125476).

2^1721536 is an apocalyptic number.

1721536 is a gapful number since it is divisible by the number (16) 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 1721536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1756664).

1721536 is an abundant number, since it is smaller than the sum of its proper divisors (1791792).

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

1721536 is an equidigital number, since it uses as much as digits as its factorization.

1721536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 776 (or 766 counting only the distinct ones).

The product of its digits is 1260, while the sum is 25.

The square root of 1721536 is about 1312.0731686914. The cubic root of 1721536 is about 119.8501834064.

The spelling of 1721536 in words is "one million, seven hundred twenty-one thousand, five hundred thirty-six".