216927720025 has 9 divisors (see below), whose sum is σ = 268993260543. Its totient is φ = 173540313000.

The previous prime is 216927720013. The next prime is 216927720047. The reversal of 216927720025 is 520027729612.

The square root of 216927720025 is 465755.

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

It can be written as a sum of positive squares in only one way, i.e., 78093979209 + 138833740816 = 279453^2 + 372604^2 .

It is a de Polignac number, because none of the positive numbers 2^k-216927720025 is a prime.

It is a Duffinian number.

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 8 ways as a sum of consecutive naturals, for example, 2282200 + ... + 2375350.

Almost surely, 2^216927720025 is an apocalyptic number.

216927720025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

216927720025 is the 465755-th square number.

216927720025 is the 232878-th centered octagonal number.

It is an amenable number.

216927720025 is a deficient number, since it is larger than the sum of its proper divisors (52065540518).

216927720025 is an frugal number, since it uses more digits than its factorization.

216927720025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186312 (or 93156 counting only the distinct ones).

The product of its (nonzero) digits is 211680, while the sum is 43.

The spelling of 216927720025 in words is "two hundred sixteen billion, nine hundred twenty-seven million, seven hundred twenty thousand, twenty-five".