25561311 has 4 divisors (see below), whose sum is σ = 34081752. Its totient is φ = 17040872.

The previous prime is 25561309. The next prime is 25561313. The reversal of 25561311 is 11316552.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (25561309) and next prime (25561313).

It is a cyclic number.

It is not a de Polignac number, because 25561311 - 2¹ = 25561309 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25561313) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4260216 + ... + 4260221.

It is an arithmetic number, because the mean of its divisors is an integer number (8520438).

Almost surely, 2^25561311 is an apocalyptic number.

25561311 is a deficient number, since it is larger than the sum of its proper divisors (8520441).

25561311 is an equidigital number, since it uses as much as digits as its factorization.

25561311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8520440.

The product of its digits is 900, while the sum is 24.

The square root of 25561311 is about 5055.8195181395. The cubic root of 25561311 is about 294.5739747276.

Adding to 25561311 its reverse (11316552), we get a palindrome (36877863).

The spelling of 25561311 in words is "twenty-five million, five hundred sixty-one thousand, three hundred eleven".