25540447 has 2 divisors, whose sum is σ = 25540448. Its totient is φ = 25540446.

The previous prime is 25540421. The next prime is 25540453. The reversal of 25540447 is 74404552.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25540447 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25540247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12770223 + 12770224.

It is an arithmetic number, because the mean of its divisors is an integer number (12770224).

Almost surely, 2^25540447 is an apocalyptic number.

25540447 is a deficient number, since it is larger than the sum of its proper divisors (1).

25540447 is an equidigital number, since it uses as much as digits as its factorization.

25540447 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 22400, while the sum is 31.

The square root of 25540447 is about 5053.7557321264. The cubic root of 25540447 is about 294.4938058563.

Adding to 25540447 its reverse (74404552), we get a palindrome (99944999).

The spelling of 25540447 in words is "twenty-five million, five hundred forty thousand, four hundred forty-seven".