1721104 has 60 divisors (see below), whose sum is σ = 4221952. Its totient is φ = 665280.

The previous prime is 1721081. The next prime is 1721123. The reversal of 1721104 is 4011271.

1721104 = T₉₇ + T₉₈ + ... + T₂₂₃.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is an Ulam number.

It is a nialpdrome in base 11.

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 13489 + ... + 13615.

2^1721104 is an apocalyptic number.

1721104 is a gapful number since it is divisible by the number (14) 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 1721104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2110976).

1721104 is an abundant number, since it is smaller than the sum of its proper divisors (2500848).

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

1721104 is a wasteful number, since it uses less digits than its factorization.

1721104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164 (or 147 counting only the distinct ones).

The product of its (nonzero) digits is 56, while the sum is 16.

The square root of 1721104 is about 1311.9085333971. The cubic root of 1721104 is about 119.8401575515.

Adding to 1721104 its reverse (4011271), we get a palindrome (5732375).

The spelling of 1721104 in words is "one million, seven hundred twenty-one thousand, one hundred four".