9809912025 has 135 divisors (see below), whose sum is σ = 19044610959. Its totient is φ = 4991868000.

The previous prime is 9809912011. The next prime is 9809912069. The reversal of 9809912025 is 5202199089.

The square root of 9809912025 is 99045.

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., 3531568329 + 6278343696 = 59427^2 + 79236^2 .

It is a tau number, because it is divible by the number of its divisors (135).

It is not a de Polignac number, because 9809912025 - 2⁹ = 9809911513 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 138167740 + ... + 138167810.

Almost surely, 2^9809912025 is an apocalyptic number.

9809912025 is the 99045-th square number.

9809912025 is the 49523-rd centered octagonal number.

It is an amenable number.

9809912025 is a deficient number, since it is larger than the sum of its proper divisors (9234698934).

9809912025 is an equidigital number, since it uses as much as digits as its factorization.

9809912025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226 (or 110 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 45.

The cubic root of 9809912025 is about 2140.6961971169.

The spelling of 9809912025 in words is "nine billion, eight hundred nine million, nine hundred twelve thousand, twenty-five".