215949807616 has 117 divisors (see below), whose sum is σ = 443384899531. Its totient is φ = 105164374016.

The previous prime is 215949807589. The next prime is 215949807617. The reversal of 215949807616 is 616708949512.

The square root of 215949807616 is 464704.

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 20939247616 + 195010560000 = 144704^2 + 441600^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215949807617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1576275900 + ... + 1576276036.

Almost surely, 2^215949807616 is an apocalyptic number.

215949807616 is the 464704-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 215949807616

215949807616 is an abundant number, since it is smaller than the sum of its proper divisors (227435091915).

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

215949807616 is an frugal number, since it uses more digits than its factorization.

215949807616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 404 (or 192 counting only the distinct ones).

The product of its (nonzero) digits is 6531840, while the sum is 58.

The spelling of 215949807616 in words is "two hundred fifteen billion, nine hundred forty-nine million, eight hundred seven thousand, six hundred sixteen".