721741709 has 12 divisors (see below), whose sum is σ = 791438400. Its totient is φ = 657777744.

The previous prime is 721741693. The next prime is 721741711. The reversal of 721741709 is 907147127.

721741709 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 721741709 - 2⁴ = 721741693 is a prime.

It is a super-2 number, since 2×721741709² = 1041822189020481362, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721741109) 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, 13679 + ... + 40380.

It is an arithmetic number, because the mean of its divisors is an integer number (65953200).

Almost surely, 2^721741709 is an apocalyptic number.

721741709 is a gapful number since it is divisible by the number (79) formed by its first and last digit.

It is an amenable number.

721741709 is a deficient number, since it is larger than the sum of its proper divisors (69696691).

721741709 is a wasteful number, since it uses less digits than its factorization.

721741709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54164 (or 54151 counting only the distinct ones).

The product of its (nonzero) digits is 24696, while the sum is 38.

The square root of 721741709 is about 26865.2509573240. The cubic root of 721741709 is about 897.0030805747.

The spelling of 721741709 in words is "seven hundred twenty-one million, seven hundred forty-one thousand, seven hundred nine".