656212323220 has 24 divisors (see below), whose sum is σ = 1379529282600. Its totient is φ = 262202376192.

The previous prime is 656212323199. The next prime is 656212323241. The reversal of 656212323220 is 22323212656.

It is an interprime number because it is at equal distance from previous prime (656212323199) and next prime (656212323241).

It can be written as a sum of positive squares in 4 ways, for example, as 14848397316 + 641363925904 = 121854^2 + 800852^2 .

It is a super-2 number, since 2×656212323220² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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, 17640525 + ... + 17677684.

It is an arithmetic number, because the mean of its divisors is an integer number (57480386775).

Almost surely, 2^656212323220 is an apocalyptic number.

It is an amenable number.

656212323220 is an abundant number, since it is smaller than the sum of its proper divisors (723316959380).

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

656212323220 is a wasteful number, since it uses less digits than its factorization.

656212323220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35319147 (or 35319145 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 34.

Adding to 656212323220 its reverse (22323212656), we get a palindrome (678535535876).

The spelling of 656212323220 in words is "six hundred fifty-six billion, two hundred twelve million, three hundred twenty-three thousand, two hundred twenty".