209612887225 has 81 divisors (see below), whose sum is σ = 307742912847. Its totient is φ = 141218290080.

The previous prime is 209612887207. The next prime is 209612887241. The reversal of 209612887225 is 522788216902.

The square root of 209612887225 is 457835.

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., 75460639401 + 134152247824 = 274701^2 + 366268^2 .

It is not a de Polignac number, because 209612887225 - 2¹³ = 209612879033 is a prime.

It is a Smith number, since the sum of its digits (52) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 1650495112 + ... + 1650495238.

Almost surely, 2^209612887225 is an apocalyptic number.

209612887225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

209612887225 is the 457835-th square number.

209612887225 is the 228918-th centered octagonal number.

It is an amenable number.

209612887225 is a deficient number, since it is larger than the sum of its proper divisors (98130025622).

209612887225 is an equidigital number, since it uses as much as digits as its factorization.

209612887225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 484 (or 242 counting only the distinct ones).

The product of its (nonzero) digits is 1935360, while the sum is 52.

The spelling of 209612887225 in words is "two hundred nine billion, six hundred twelve million, eight hundred eighty-seven thousand, two hundred twenty-five".