721311040 has 28 divisors (see below), whose sum is σ = 1717622676. Its totient is φ = 288524288.

The previous prime is 721311013. The next prime is 721311067. The reversal of 721311040 is 40113127.

721311040 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (721311013) and next prime (721311067).

It can be written as a sum of positive squares in 2 ways, for example, as 114575616 + 606735424 = 10704^2 + 24632^2 .

It is a junction number, because it is equal to n+sod(n) for n = 721310999 and 721311017.

It is a congruent 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, 1126729 + ... + 1127368.

It is an arithmetic number, because the mean of its divisors is an integer number (61343667).

Almost surely, 2^721311040 is an apocalyptic number.

It is an amenable number.

721311040 is an abundant number, since it is smaller than the sum of its proper divisors (996311636).

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

721311040 is a wasteful number, since it uses less digits than its factorization.

721311040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2254114 (or 2254104 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 19.

The square root of 721311040 is about 26857.2344071388. The cubic root of 721311040 is about 896.8246287922.

Adding to 721311040 its reverse (40113127), we get a palindrome (761424167).

The spelling of 721311040 in words is "seven hundred twenty-one million, three hundred eleven thousand, forty".