721956522 has 64 divisors (see below), whose sum is σ = 1726433280. Its totient is φ = 196789824.

The previous prime is 721956497. The next prime is 721956523. The reversal of 721956522 is 225659127.

It is not an unprimeable number, because it can be changed into a prime (721956523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 504504 + ... + 505932.

It is an arithmetic number, because the mean of its divisors is an integer number (26975520).

Almost surely, 2^721956522 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 721956522, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (863216640).

721956522 is an abundant number, since it is smaller than the sum of its proper divisors (1004476758).

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

721956522 is a wasteful number, since it uses less digits than its factorization.

721956522 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1987.

The product of its digits is 75600, while the sum is 39.

The square root of 721956522 is about 26869.2486311024. The cubic root of 721956522 is about 897.0920638434.

The spelling of 721956522 in words is "seven hundred twenty-one million, nine hundred fifty-six thousand, five hundred twenty-two".