1239804306225 has 27 divisors (see below), whose sum is σ = 2220657183979. Its totient is φ = 661220055600.

The previous prime is 1239804306217. The next prime is 1239804306227. The reversal of 1239804306225 is 5226034089321.

The square root of 1239804306225 is 1113465.

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

1239804306225 is a `hidden beast` number, since 1 + 2 + 398 + 0 + 4 + 30 + 6 + 225 = 666.

It can be written as a sum of positive squares in only one way, i.e., 446329550241 + 793474755984 = 668079^2 + 890772^2 .

It is not a de Polignac number, because 1239804306225 - 2³ = 1239804306217 is a prime.

It is a super-2 number, since 2×1239804306225² (a number of 25 digits) contains 22 as substring.

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

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1239804306227) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 16664860 + ... + 16739090.

Almost surely, 2^{1239804306225} is an apocalyptic number.

1239804306225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1239804306225 is the 1113465-th square number.

1239804306225 is the 556733-rd centered octagonal number.

It is an amenable number.

1239804306225 is a deficient number, since it is larger than the sum of its proper divisors (980852877754).

1239804306225 is an frugal number, since it uses more digits than its factorization.

1239804306225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148478 (or 74239 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 45.

The spelling of 1239804306225 in words is "one trillion, two hundred thirty-nine billion, eight hundred four million, three hundred six thousand, two hundred twenty-five".