219806257225 has 27 divisors (see below), whose sum is σ = 279491908341. Its totient is φ = 171481089600.

The previous prime is 219806257217. The next prime is 219806257249. The reversal of 219806257225 is 522752608912.

The square root of 219806257225 is 468835.

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 92519997241 + 127286259984 = 304171^2 + 356772^2 .

It is not a de Polignac number, because 219806257225 - 2³ = 219806257217 is a prime.

It is a super-3 number, since 3×219806257225³ (a number of 35 digits) contains 333 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 96110032 + ... + 96112318.

Almost surely, 2^219806257225 is an apocalyptic number.

219806257225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

219806257225 is the 468835-th square number.

219806257225 is the 234418-th centered octagonal number.

It is an amenable number.

219806257225 is a deficient number, since it is larger than the sum of its proper divisors (59685651116).

219806257225 is an frugal number, since it uses more digits than its factorization.

219806257225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4666 (or 2333 counting only the distinct ones).

The product of its (nonzero) digits is 1209600, while the sum is 49.

Multiplying 219806257225 by its sum of digits (49), we get a square (10770506604025 = 3281845²).

The spelling of 219806257225 in words is "two hundred nineteen billion, eight hundred six million, two hundred fifty-seven thousand, two hundred twenty-five".