721235 has 4 divisors (see below), whose sum is σ = 865488. Its totient is φ = 576984.

The previous prime is 721229. The next prime is 721243. The reversal of 721235 is 532127.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 532127 = 401 ⋅1327.

It is a cyclic number.

It is not a de Polignac number, because 721235 - 2⁴ = 721219 is a prime.

It is a Duffinian number.

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, 72119 + ... + 72128.

It is an arithmetic number, because the mean of its divisors is an integer number (216372).

2⁷²¹²³⁵ is an apocalyptic number.

721235 is a deficient number, since it is larger than the sum of its proper divisors (144253).

721235 is a wasteful number, since it uses less digits than its factorization.

721235 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144252.

The product of its digits is 420, while the sum is 20.

The square root of 721235 is about 849.2555563551. The cubic root of 721235 is about 89.6793113520.

The spelling of 721235 in words is "seven hundred twenty-one thousand, two hundred thirty-five".