805721720120 has 32 divisors (see below), whose sum is σ = 1813083916320. Its totient is φ = 322251346560.

The previous prime is 805721720107. The next prime is 805721720123. The reversal of 805721720120 is 21027127508.

It is a super-2 number, since 2×805721720120² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (805721720123) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 816071 + ... + 1509110.

It is an arithmetic number, because the mean of its divisors is an integer number (56658872385).

Almost surely, 2^805721720120 is an apocalyptic number.

It is an amenable number.

805721720120 is an abundant number, since it is smaller than the sum of its proper divisors (1007362196200).

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

805721720120 is a wasteful number, since it uses less digits than its factorization.

805721720120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2333855 (or 2333851 counting only the distinct ones).

The product of its (nonzero) digits is 15680, while the sum is 35.

Adding to 805721720120 its reverse (21027127508), we get a palindrome (826748847628).

The spelling of 805721720120 in words is "eight hundred five billion, seven hundred twenty-one million, seven hundred twenty thousand, one hundred twenty".