122720256 has 78 divisors (see below), whose sum is σ = 354588390. Its totient is φ = 40894464.

The previous prime is 122720251. The next prime is 122720261. The reversal of 122720256 is 652027221.

It is an interprime number because it is at equal distance from previous prime (122720251) and next prime (122720261).

It can be written as a sum of positive squares in only one way, i.e., 99680256 + 23040000 = 9984^2 + 4800^2 .

It is a super-2 number, since 2×122720256² = 30120522465411072, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (122720251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35200 + ... + 38528.

It is an arithmetic number, because the mean of its divisors is an integer number (4546005).

Almost surely, 2^122720256 is an apocalyptic number.

122720256 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 122720256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (177294195).

122720256 is an abundant number, since it is smaller than the sum of its proper divisors (231868134).

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

122720256 is an equidigital number, since it uses as much as digits as its factorization.

122720256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3359 (or 3334 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 122720256 is about 11077.9174938253. The cubic root of 122720256 is about 496.9416727430.

Adding to 122720256 its reverse (652027221), we get a palindrome (774747477).

The spelling of 122720256 in words is "one hundred twenty-two million, seven hundred twenty thousand, two hundred fifty-six".