25499987 has 2 divisors, whose sum is σ = 25499988. Its totient is φ = 25499986.

The previous prime is 25499963. The next prime is 25500001. The reversal of 25499987 is 78999452.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 25499987 - 2²⁰ = 24451411 is a prime.

It is not a weakly prime, because it can be changed into another prime (25499927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12749993 + 12749994.

It is an arithmetic number, because the mean of its divisors is an integer number (12749994).

Almost surely, 2^25499987 is an apocalyptic number.

25499987 is a deficient number, since it is larger than the sum of its proper divisors (1).

25499987 is an equidigital number, since it uses as much as digits as its factorization.

25499987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1632960, while the sum is 53.

The square root of 25499987 is about 5049.7511819891. The cubic root of 25499987 is about 294.3382158259.

The spelling of 25499987 in words is "twenty-five million, four hundred ninety-nine thousand, nine hundred eighty-seven".