215564243554 has 12 divisors (see below), whose sum is σ = 355413773862. Its totient is φ = 97983746960.

The previous prime is 215564243551. The next prime is 215564243611. The reversal of 215564243554 is 455342465512.

It can be written as a sum of positive squares in only one way, i.e., 178486815529 + 37077428025 = 422477^2 + 192555^2 .

It is not an unprimeable number, because it can be changed into a prime (215564243551) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 445380427 + ... + 445380910.

Almost surely, 2^215564243554 is an apocalyptic number.

215564243554 is a deficient number, since it is larger than the sum of its proper divisors (139849530308).

215564243554 is a wasteful number, since it uses less digits than its factorization.

215564243554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 890761361 (or 890761350 counting only the distinct ones).

The product of its digits is 2880000, while the sum is 46.

The spelling of 215564243554 in words is "two hundred fifteen billion, five hundred sixty-four million, two hundred forty-three thousand, five hundred fifty-four".