215559632656 has 135 divisors (see below), whose sum is σ = 454850739903. Its totient is φ = 98948206080.

The previous prime is 215559632557. The next prime is 215559632711. The reversal of 215559632656 is 656236955512.

The square root of 215559632656 is 464284.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 152658992656 + 62900640000 = 390716^2 + 250800^2 .

It is a super-2 number, since 2×215559632656² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 215559632597 and 215559632606.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1446708870 + ... + 1446709018.

Almost surely, 2^215559632656 is an apocalyptic number.

215559632656 is the 464284-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 215559632656

215559632656 is an abundant number, since it is smaller than the sum of its proper divisors (239291107247).

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

215559632656 is an equidigital number, since it uses as much as digits as its factorization.

215559632656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 426 (or 211 counting only the distinct ones).

The product of its digits is 14580000, while the sum is 55.

The spelling of 215559632656 in words is "two hundred fifteen billion, five hundred fifty-nine million, six hundred thirty-two thousand, six hundred fifty-six".