25939698168609 has 9 divisors (see below), whose sum is σ = 37468474980339. Its totient is φ = 17293121926200.

The previous prime is 25939698168583. The next prime is 25939698168611. The reversal of 25939698168609 is 90686189693952.

The square root of 25939698168609 is 5093103.

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

25939698168609 is a `hidden beast` number, since 2 + 5 + 9 + 396 + 9 + 8 + 168 + 60 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 12478577445009 + 13461120723600 = 3532503^2 + 3668940^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 25939698168609 - 2¹³ = 25939698160417 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25939698168689) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 14430459 + ... + 16128159.

Almost surely, 2^{25939698168609} is an apocalyptic number.

25939698168609 is the 5093103-rd square number.

25939698168609 is the 2546552-nd centered octagonal number.

It is an amenable number.

25939698168609 is a deficient number, since it is larger than the sum of its proper divisors (11528776811730).

25939698168609 is an frugal number, since it uses more digits than its factorization.

25939698168609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3395408 (or 1697704 counting only the distinct ones).

The product of its (nonzero) digits is 2720977920, while the sum is 81.

The spelling of 25939698168609 in words is "twenty-five trillion, nine hundred thirty-nine billion, six hundred ninety-eight million, one hundred sixty-eight thousand, six hundred nine".