25705281 has 16 divisors (see below), whose sum is σ = 40521600. Its totient is φ = 14181888.

The previous prime is 25705279. The next prime is 25705289. The reversal of 25705281 is 18250752.

It is not a de Polignac number, because 25705281 - 2¹ = 25705279 is a prime.

It is a super-2 number, since 2×25705281² = 1321522942577922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (25705289) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20496 + ... + 21713.

It is an arithmetic number, because the mean of its divisors is an integer number (2532600).

Almost surely, 2^25705281 is an apocalyptic number.

25705281 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

25705281 is a deficient number, since it is larger than the sum of its proper divisors (14816319).

25705281 is a wasteful number, since it uses less digits than its factorization.

25705281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42248.

The product of its (nonzero) digits is 5600, while the sum is 30.

The square root of 25705281 is about 5070.0375738253. The cubic root of 25705281 is about 295.1259865967.

The spelling of 25705281 in words is "twenty-five million, seven hundred five thousand, two hundred eighty-one".