25918281 has 9 divisors (see below), whose sum is σ = 37459591. Its totient is φ = 17268672.

The previous prime is 25918259. The next prime is 25918283. The reversal of 25918281 is 18281952.

The square root of 25918281 is 5091.

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., 24950025 + 968256 = 4995^2 + 984^2 .

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

It is not a de Polignac number, because 25918281 - 2⁷ = 25918153 is a prime.

It is a super-2 number, since 2×25918281² = 1343514579989922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (25918283) 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, 14425 + ... + 16121.

Almost surely, 2^25918281 is an apocalyptic number.

25918281 is the 5091-st square number.

25918281 is the 2546-th centered octagonal number.

It is an amenable number.

25918281 is a deficient number, since it is larger than the sum of its proper divisors (11541310).

25918281 is an frugal number, since it uses more digits than its factorization.

25918281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3400 (or 1700 counting only the distinct ones).

The product of its digits is 11520, while the sum is 36.

The cubic root of 25918281 is about 295.9389064624.

Multiplying 25918281 by its sum of digits (36), we get a square (933058116 = 30546²).

The spelling of 25918281 in words is "twenty-five million, nine hundred eighteen thousand, two hundred eighty-one".