25640143 has 4 divisors (see below), whose sum is σ = 25667008. Its totient is φ = 25613280.

The previous prime is 25640081. The next prime is 25640171. The reversal of 25640143 is 34104652.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25640143 is a prime.

It is a Duffinian number.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25640183) 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, 11946 + ... + 13927.

It is an arithmetic number, because the mean of its divisors is an integer number (6416752).

Almost surely, 2^25640143 is an apocalyptic number.

25640143 is a deficient number, since it is larger than the sum of its proper divisors (26865).

25640143 is an equidigital number, since it uses as much as digits as its factorization.

25640143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26864.

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 25640143 is about 5063.6096808502. The cubic root of 25640143 is about 294.8764895197.

Adding to 25640143 its reverse (34104652), we get a palindrome (59744795).

The spelling of 25640143 in words is "twenty-five million, six hundred forty thousand, one hundred forty-three".