721721862 has 12 divisors (see below), whose sum is σ = 1563730740. Its totient is φ = 240573948.

The previous prime is 721721851. The next prime is 721721863. The reversal of 721721862 is 268127127.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721721863) 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 5 ways as a sum of consecutive naturals, for example, 20047812 + ... + 20047847.

It is an arithmetic number, because the mean of its divisors is an integer number (130310895).

Almost surely, 2^721721862 is an apocalyptic number.

721721862 is an abundant number, since it is smaller than the sum of its proper divisors (842008878).

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

721721862 is a wasteful number, since it uses less digits than its factorization.

721721862 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40095667 (or 40095664 counting only the distinct ones).

The product of its digits is 18816, while the sum is 36.

The square root of 721721862 is about 26864.8815742783. The cubic root of 721721862 is about 896.9948583427.

Adding to 721721862 its reverse (268127127), we get a palindrome (989848989).

The spelling of 721721862 in words is "seven hundred twenty-one million, seven hundred twenty-one thousand, eight hundred sixty-two".