721084 has 36 divisors (see below), whose sum is σ = 1586424. Its totient is φ = 284256.

The previous prime is 721079. The next prime is 721087. The reversal of 721084 is 480127.

721084 = T₁₆ + T₁₇ + ... + T₁₆₂.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721087) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2407 + ... + 2689.

2⁷²¹⁰⁸⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 721084, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (793212).

721084 is an abundant number, since it is smaller than the sum of its proper divisors (865340).

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

721084 is a wasteful number, since it uses less digits than its factorization.

721084 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 314 (or 305 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 721084 is about 849.1666503108. The cubic root of 721084 is about 89.6730524021.

It can be divided in two parts, 72 and 1084, that added together give a square (1156 = 34²).

The spelling of 721084 in words is "seven hundred twenty-one thousand, eighty-four".