215531776516 has 27 divisors (see below), whose sum is σ = 438774348117. Its totient is φ = 92367975840.

The previous prime is 215531776489. The next prime is 215531776519. The reversal of 215531776516 is 615677135512.

The square root of 215531776516 is 464254.

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

215531776516 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 205257926916 + 10273849600 = 453054^2 + 101360^2 .

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a self number, because there is not a number n which added to its sum of digits gives 215531776516.

It is not an unprimeable number, because it can be changed into a prime (215531776519) by changing a digit.

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 8 ways as a sum of consecutive naturals, for example, 6482976 + ... + 6516136.

Almost surely, 2^215531776516 is an apocalyptic number.

215531776516 is the 464254-th square number.

It is an amenable number.

215531776516 is an abundant number, since it is smaller than the sum of its proper divisors (223242571601).

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

215531776516 is an frugal number, since it uses more digits than its factorization.

215531776516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66340 (or 33170 counting only the distinct ones).

The product of its digits is 1323000, while the sum is 49.

Multiplying 215531776516 by its sum of digits (49), we get a square (10561057049284 = 3249778²).

215531776516 divided by its sum of digits (49) gives a square (4398607684 = 66322²).

The spelling of 215531776516 in words is "two hundred fifteen billion, five hundred thirty-one million, seven hundred seventy-six thousand, five hundred sixteen".