721375 has 16 divisors (see below), whose sum is σ = 936000.
Its totient is φ = 554400.
The previous prime is 721363. The next prime is 721379. The reversal of 721375 is 573127.
It is not a de Polignac number, because 721375 - 213 = 713183 is a prime.
It is a Harshad number since it is a multiple of its sum of digits (25).
It is a d-powerful number, because it can be written as 7 + 219 + 311 + 1 + 75 + 55 .
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (721379) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (11) of ones.
It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3526 + ... + 3724.
It is an arithmetic number, because the mean of its divisors is an integer number (58500).
2721375 is an apocalyptic number.
721375 is a deficient number, since it is larger than the sum of its proper divisors (214625).
721375 is a wasteful number, since it uses less digits than its factorization.
721375 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 243 (or 233 counting only the distinct ones).
The product of its digits is 1470, while the sum is 25.
The square root of 721375 is about 849.3379774860.
The cubic root of 721375 is about 89.6851135715.
The spelling of 721375 in words is "seven hundred twenty-one thousand, three hundred seventy-five".