721024 has 32 divisors (see below), whose sum is σ = 1481040. Its totient is φ = 349440.

The previous prime is 721013. The next prime is 721037. The reversal of 721024 is 420127.

It is a tau number, because it is divible by the number of its divisors (32).

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

It is a junction number, because it is equal to n+sod(n) for n = 720989 and 721007.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5439 + ... + 5569.

2⁷²¹⁰²⁴ 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 721024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (740520).

721024 is an abundant number, since it is smaller than the sum of its proper divisors (760016).

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

721024 is a wasteful number, since it uses less digits than its factorization.

721024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188 (or 176 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 16.

The square root of 721024 is about 849.1313208215. The cubic root of 721024 is about 89.6705651596.

The spelling of 721024 in words is "seven hundred twenty-one thousand, twenty-four", and thus it is an iban number.