999999266245225 has 9 divisors (see below), whose sum is σ = 1239999286205253. Its totient is φ = 799999286505120.

The previous prime is 999999266245193. The next prime is 999999266245241. The reversal of 999999266245225 is 522542662999999.

The square root of 999999266245225 is 31622765.

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 421897063657689 + 578102202587536 = 20540133^2 + 24043756^2 .

It is not a de Polignac number, because 999999266245225 - 2⁵ = 999999266245193 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 154951549 + ... + 161276101.

Almost surely, 2^{999999266245225} is an apocalyptic number.

999999266245225 is the 31622765-th square number.

999999266245225 is the 15811383-rd centered octagonal number.

It is an amenable number.

999999266245225 is a deficient number, since it is larger than the sum of its proper divisors (240000019960028).

999999266245225 is an frugal number, since it uses more digits than its factorization.

999999266245225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12649116 (or 6324558 counting only the distinct ones).

The product of its digits is 30611001600, while the sum is 88.

The spelling of 999999266245225 in words is "nine hundred ninety-nine trillion, nine hundred ninety-nine billion, two hundred sixty-six million, two hundred forty-five thousand, two hundred twenty-five".