721055144240 has 20 divisors (see below), whose sum is σ = 1676453210544. Its totient is φ = 288422057664.

The previous prime is 721055144237. The next prime is 721055144267. The reversal of 721055144240 is 42441550127.

It is a tau number, because it is divible by the number of its divisors (20).

It is a self number, because there is not a number n which added to its sum of digits gives 721055144240.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4506594572 + ... + 4506594731.

Almost surely, 2^721055144240 is an apocalyptic number.

It is an amenable number.

721055144240 is an abundant number, since it is smaller than the sum of its proper divisors (955398066304).

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

721055144240 is a wasteful number, since it uses less digits than its factorization.

721055144240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9013189316 (or 9013189310 counting only the distinct ones).

The product of its (nonzero) digits is 44800, while the sum is 35.

Adding to 721055144240 its reverse (42441550127), we get a palindrome (763496694367).

The spelling of 721055144240 in words is "seven hundred twenty-one billion, fifty-five million, one hundred forty-four thousand, two hundred forty".