25491487 has 4 divisors (see below), whose sum is σ = 29133136. Its totient is φ = 21849840.

The previous prime is 25491467. The next prime is 25491523. The reversal of 25491487 is 78419452.

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

It is a cyclic number.

It is not a de Polignac number, because 25491487 - 2¹¹ = 25489439 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25491457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1820814 + ... + 1820827.

It is an arithmetic number, because the mean of its divisors is an integer number (7283284).

Almost surely, 2^25491487 is an apocalyptic number.

25491487 is a deficient number, since it is larger than the sum of its proper divisors (3641649).

25491487 is an equidigital number, since it uses as much as digits as its factorization.

25491487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3641648.

The product of its digits is 80640, while the sum is 40.

The square root of 25491487 is about 5048.9094862158. The cubic root of 25491487 is about 294.3055079285.

The spelling of 25491487 in words is "twenty-five million, four hundred ninety-one thousand, four hundred eighty-seven".