722784640 has 128 divisors (see below), whose sum is σ = 1795828320. Its totient is φ = 277954560.

The previous prime is 722784577. The next prime is 722784641. The reversal of 722784640 is 46487227.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 722784593 and 722784602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (722784641) 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, 3101964 + ... + 3102196.

Almost surely, 2^722784640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 722784640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (897914160).

722784640 is an abundant number, since it is smaller than the sum of its proper divisors (1073043680).

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

722784640 is a wasteful number, since it uses less digits than its factorization.

722784640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 420 (or 408 counting only the distinct ones).

The product of its (nonzero) digits is 150528, while the sum is 40.

The square root of 722784640 is about 26884.6543589461. The cubic root of 722784640 is about 897.4349350079.

The spelling of 722784640 in words is "seven hundred twenty-two million, seven hundred eighty-four thousand, six hundred forty".